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Sample records for pillar lignite mines

  1. The effect of the depth and groundwater on the formation of sinkholes or ground subsidence associated with abandoned room and pillar lignite mines under static and dynamic conditions

    Directory of Open Access Journals (Sweden)

    Ö. Aydan

    2015-11-01

    Full Text Available It is well known that some sinkholes or subsidence take place from time to time in the areas where abandoned room and pillar type mines exist. The author has been involved with the stability of abandoned mines beneath urbanized residential areas in Tokai region and there is a great concern about the stability of these abandoned mines during large earthquakes as well as in the long term. The 2003 Miyagi Hokubu and 2011 Great East Japan earthquakes caused great damage to abandoned mines and resulted in many collapses. The author presents the effect of the depth and groundwater on the formation of sinkholes or ground subsidence associated with abandoned room and pillar lignite mines under static and dynamic conditions and discusses the implications on the areas above abandoned lignite mines in this paper.

  2. Some examples of the cavity filling along transportation routes above abandoned room and pillar lignite Mines in Tokai Region

    International Nuclear Information System (INIS)

    Sakamoto, A.; Yamada, N.; Sugiura, K.; Kawamoto, T.

    2005-01-01

    The authors describe the applications of the integrated cavity filling technique to abandoned lignite mines in Tokai region. These abandoned lignite mines were in operation until 1960's and the routes of Tokai By-Pass Expressway and the linear motor car railway line for Aichi Exposition pass over these abandoned mines. Since the size of abandoned mines were much larger than the route of the expressway and the elevated monorail, limited areas relevant to their stability had to be only filled. This article describe the details of cavity filling operations in these two projects, which may be some valuable examples for assessing the methods how to deal problems associated with mine closures in long term. (authors)

  3. A real-time monitoring system for the assessment of stability and performance of in abandoned room and pillar lignite mines

    International Nuclear Information System (INIS)

    Aydan, O.; Tano, H.; Sakamoto, A.; Yamada, N.; Sugiura, K.

    2005-01-01

    The authors have been involved with the stability of abandoned mines beneath urbanized residential areas in Tokai region. These abandoned lignite mines were in operation until 1960's. There is a great concern about the stability of these abandoned mines during large earthquakes. The 2003 Miyagi Hokubu earthquake caused great damage to abandoned mines and resulted in collapses. The authors describe an integrated real-time monitoring system and they report some measured data up to now. The responses of monitoring system during a large roof collapse under gravitational condition as well as during and after two earthquakes are presented and their implications are discussed. (authors)

  4. A real-time monitoring system for the assessment of stability and performance of in abandoned room and pillar lignite mines

    Energy Technology Data Exchange (ETDEWEB)

    Aydan, O. [Tokai Univ., Dept.of Marine Civil Engineering, Shizuoka (Japan); Tano, H. [Nihon Univ., Dept. of Civil Engineering, Koriyama (Japan); Sakamoto, A.; Yamada, N.; Sugiura, K. [Tobishima Construction Company, Nagoya Branch (Japan)

    2005-07-01

    The authors have been involved with the stability of abandoned mines beneath urbanized residential areas in Tokai region. These abandoned lignite mines were in operation until 1960's. There is a great concern about the stability of these abandoned mines during large earthquakes. The 2003 Miyagi Hokubu earthquake caused great damage to abandoned mines and resulted in collapses. The authors describe an integrated real-time monitoring system and they report some measured data up to now. The responses of monitoring system during a large roof collapse under gravitational condition as well as during and after two earthquakes are presented and their implications are discussed. (authors)

  5. Expansion of Neyveli lignite mines

    Energy Technology Data Exchange (ETDEWEB)

    Kasturi, T S

    1982-06-01

    This paper describes activities at Neyveli lignite mines in the Tamil Nadu region of India. The equipment used, in mining and materials handling is described. Problems encountered in the conveyor transport system are described, and the solutions finally adopted are presented.

  6. Lignite mining in India - technology highlights

    Energy Technology Data Exchange (ETDEWEB)

    Tandon, G L

    1984-01-01

    Figures for lignite production and its role in the Indian energy scene are presented. Lignite mining at Neyveli is described in detail, including: advance preparation of the overburden strata; modifications to bucket wheel excavators; tackling the sticky surface clays; ground water management; storm water control; tackling higher overburden-to-lignite ratios; materials handling; communications within the mine; the development of indigenous mining equipment; and ecology and environmental control.

  7. Expansion of the Neyveli lignite mine, India

    Energy Technology Data Exchange (ETDEWEB)

    Kasturi, T S [Neyveli Lignite Corp. Ltd., Tamil Nadu (India); Streck, W [Gold (O.) G.m.b.H. und Co. K.G., Koeln (Germany, F.R.)

    1979-08-01

    After giving a picture of the difficult winning conditions at the Neyveli open-cast lignite mine, the author states the reasons for the expansions of the open-cast mine and describes the necessary measures and machinery.

  8. Rapid restoration after lignite mining in Hungary

    Energy Technology Data Exchange (ETDEWEB)

    1988-06-01

    The 30th anniversary of the commencement of large scale lignite production by opencast mining in Hungary was celebrated in 1987. A process of rapid technical and biological reclamation without the use of humus has now been developed. The costs involved are only 5-10% of those of conventional methods and reclamation cycle is four years compared to ten years for conventional methods.

  9. Externalities from lignite mining-related dust emissions

    International Nuclear Information System (INIS)

    Papagiannis, A.; Roussos, D.; Menegaki, M.; Damigos, D.

    2014-01-01

    During the last three decades, several studies have been conducted in order to assess the external costs of electricity production from fossil fuels, especially coal and lignite. Nevertheless, these studies usually ignore the impacts generated by the upstream mining works. This paper contributes to existing literature and attempts to fill this gap by exploring the externalities of lignite mining owing to the emission of suspended particulate matter. To this end, a ‘bottom-up’ approach is implemented, using as case study the largest operational lignite surface mine at the Lignite Center of Western Macedonia (Greece). The results indicate that annual air pollution externalities of lignite mining are of the order of 3€/ton of lignite, which corresponds to around 5.0 €/MW h. The estimated costs are significantly lower, i.e. up to 80%, when dust deposition is considered in air dispersion models. In any case, these findings should be seen as a starting point for discussion owing to the lack of specific emission rates for Greek lignite mines. - Highlights: • Externalities from lignite mining-related dust emissions are 3 €/t of lignite. • Externalities of mining correspond to around 5.0 €/MW h. • Externalities are significantly lower, up to 80%, if dust deposition is considered. • There is lack of specific dust emission rates for lignite mining. • There are high discrepancies in existing dust emission rates for lignite mining

  10. Selective coal mining of intercalated lignite deposits

    Energy Technology Data Exchange (ETDEWEB)

    Zunic, R [Kolubara-Projekt, Lazarevac (Yugoslavia)

    1991-01-01

    Describes selective coal mining in the Tamnava-Istocno Polje coal surface coal mine (Yugoslavia), designed for an annual coal production of 11.4 Mt. Until 1991, this mine exploited one thick lignite seam, without spoil intercalations, using a bucket wheel excavator-conveyor-spreader system both for coal mining and removal of overburden. In the future, several spoil intercalations of up to 1.0 m and thicker will appear with a total volume of 22 million m{sup 3}. These intercalations have to be selectively excavated in order to guarantee the calorific value of coal for the Nikola Tesla power plant. Computer calculations were carried out to determine the decrease in excavator coal production due to selective mining of spoil strata. Calculations found that the annual surface mine capacity will be lower by at most 9%, depending on thickness of spoil intercalations. The useful operation time of excavators will be reduced by 98 hours per year. The planned annual coal production will nevertheless be fulfilled. 3 refs.

  11. Sustainable Mining Land Use for Lignite Based Energy Projects

    Science.gov (United States)

    Dudek, Michal; Krysa, Zbigniew

    2017-12-01

    This research aims to discuss complex lignite based energy projects economic viability and its impact on sustainable land use with respect to project risk and uncertainty, economics, optimisation (e.g. Lerchs and Grossmann) and importance of lignite as fuel that may be expressed in situ as deposit of energy. Sensitivity analysis and simulation consist of estimated variable land acquisition costs, geostatistics, 3D deposit block modelling, electricity price considered as project product price, power station efficiency and power station lignite processing unit cost, CO2 allowance costs, mining unit cost and also lignite availability treated as lignite reserves kriging estimation error. Investigated parameters have nonlinear influence on results so that economically viable amount of lignite in optimal pit varies having also nonlinear impact on land area required for mining operation.

  12. Long-Term Stability Evaluation and Pillar Design Criterion for Room-and-Pillar Mines

    Directory of Open Access Journals (Sweden)

    Yang Yu

    2017-10-01

    Full Text Available The collapse of abandoned room-and-pillar mines is often violent and unpredictable. Safety concerns often resulted in mine closures with no post-mining stability evaluations. As a result, large amounts of land resources over room-and-pillar mines are wasted. This paper attempts to establish an understanding of the long-term stability issues of goafs (abandoned mines. Considering progressive pillar failures and the effect of single pillar failure on surrounding pillars, this paper proposes a pillar peeling model to evaluate the long-term stability of coal mines and the associated criteria for evaluating the long-term stability of room-and-pillar mines. The validity of the peeling model was verified by numerical simulation, and field data from 500 pillar cases from China, South Africa, and India. It is found that the damage level of pillar peeling is affected by the peel angle and pillar height and is controlled by the pillar width–height ratio.

  13. Lignite mining in India - thirty years of rich experience

    Energy Technology Data Exchange (ETDEWEB)

    Tandon, G L

    1984-11-01

    Exploration of the huge deposits of lignite at Neyveli in Tamil Nadu commenced in 1961 by the opencast method by deploying continuously operating machinery such as bucket-wheel excavators, spreaders and high-speed belt conveyor systems. Adoption of this mining technology to suit the peculiar site conditions at Neyveli has led to many modifications in the equipment and has enriched the experience of the Neyveli Lignite Corporation. This has also made it possible for NLC to formulate schemes for exploration and exploitation of lignite deposits occurring elsewhere in the country.

  14. Lignite mining in India - thirty years of rich experience

    Energy Technology Data Exchange (ETDEWEB)

    Tandon, G L

    1984-11-01

    Exploitation of the huge deposits of lignite at Neyveli in Tamil Nadu commenced in 1961 by opencast method by deploying continuously operating machinery such as bucket-wheel excavators, headers and high speed belt conveyor systems. Adoption of this mining technology to suit the peculiar site conditions at Neyveli has led to many modifications in the equipment and has enriched the experience of the Neyveli Lignite Corporation. This has also made it possible for NLC to formulate schemes for exploration and exploitation of lignite deposits occurring elsewhere in the country.

  15. Comparative study of German and Greek lignite mine reclamation

    International Nuclear Information System (INIS)

    Dietrich, N.L.

    1994-01-01

    The reclamation planning of three European lignite mining districts are compared: amount and extent of planning, integration with mining operations, and results. The districts are: Rheinbraun (Cologne), Leipzig-Borna (''East'' Germany), and Megalopolis (Greece). Lignite mines were visited and mining and reclamation personnel interviewed. The Rheinbraun mines have the most thorough reclamation operations. The integrated mine and reclamation operations are world class in size, scope, and detail of reclamation. A comprehensive landscape and reclamation plan is required in the mine permitting process. The Leipzig-Borna district is the second largest of the districts, studied little pre-mining planning of the post-mining landscape or land uses was evident. Reclamation is not closely integrated with the mining and typically occurs many years after the mining. Reduced lignite production since German reunification has left vast areas of disturbed land with little mining; and no funding for the reclamation of the large areas of mined land reclamation. The Greek Megalopolis mines have mine operations plan, but with no integrated reclamation planning. The initial spoil pile was reclaimed according to the original German mining plan. No pits have been reclaimed, and spoil areas are revegetated sporadically. The Rheinbraun mining operations Cologne which include a post mining landscape/land use plan have integrated and timely reclamation operations. The other two mining operations, which do not have a comprehensive and detailed reclamation and landscape/land use plans, do not integrate reclamation operations with the mining operations. The results are large areas of mined land unreclaimed for many years

  16. Australian opencast-lignite mine Yallourn; Der australische Braunkohlentagebau Yallourn

    Energy Technology Data Exchange (ETDEWEB)

    Koscierski, Marcin; Goerlich, Michael [RWTH Aachen (Germany). Inst. fuer Bergbaukunde I

    2009-01-15

    This article is about the open pit lignite mine Yallourn, located 150 km southeast of Melbourne (Figure 1). It focuses on the history, the geology and the environment. Furthermore, it describes the new mining method using large carry dozers. The open pit and the power plant are owned by TruEnergy (part of the CLP Group) and the mining activities are carried out in an Alliance with Roche Thiess Linfox (RTL). (orig.)

  17. Barrier pillar between production panels in coal mine

    Energy Technology Data Exchange (ETDEWEB)

    Zingano, Andre Cezar; Koppe, Jair Carlos; Costa, Joao Felipe C.L. [Universidade Federal do Rio Grande do Sul, Porto Alegre (Brazil)

    2007-07-01

    The function of the barrier pillar is to protect the mining panel in activity from the abutment load of adjacent mining panels that were mined. In the case of underground mines in Santa Catarina State, the barrier pillar has functioned to protect the main entries of the mine against pillar failure from old mining panels. The objective of this paper is to verify the application of the empirical method to design barrier pillars as proposed by Peng (1986), using numerical simulation following the mining geometry of the coal mines in Santa Catarina State. Two-dimensional numerical models were built taking into account the geometry of the main entries and mining panels for different overburden thickness, and considering the geomechanical properties for the rock mass that forms the roof-pillar-floor system for the Bonito coal vein. The results of the simulations showed that the empirical method to determine the barrier pillar width is valid for the studied coal vein and considered mine geometry. Neither did the pillar at the main entry become overstressed due to adjacent mine panels, nor did the roof present any failure due to stress redistribution. 9 refs., 6 figs., 5 tabs.

  18. Radon measurements concerning engineering-geological problems in lignite mining

    Energy Technology Data Exchange (ETDEWEB)

    Heinicke, J

    1986-07-01

    Radon measurements have been carried out by the aid of solid-state track detectors at the highwall of a lignite mine in order to forecast the eventual course of a landslide. The measured radon distributions and their changes as a function of time indicated that the slope was geodynamically active, but it was not possible to forecast the rate of sliding.

  19. Reclamation of a uraniferous lignite mine, North Dakota: summary paper

    International Nuclear Information System (INIS)

    Houghton, R.L.; Hall, R.L.; Unseth, J.D.; Wald, J.D.; Burgess, J.L.; Patrick, D.P.; Anderson, G.S.; Hill, S.R.

    1987-01-01

    Uraniferous lignite deposits were mined from 1955 to 1967 by surface mining techniques. Overburden was stripped, and the lignite was burned to concentrate the uranium in its ash. Uranium salts in the overburden gave exposure levels of as much as 500 microroentgens/hour; water in mine pits had U concentrations from 12 to 19,000 micrograms/liter. Reclamation involved replacing the spoils into the source pit, the most contaminated spoils being placed above the water table, capping the pit with clay then topsoil containing lesser concentrations of radioactive elements, and finally planting with prairie grass. Resulting concentrations of radionuclides are given. The land is expected to remain as prairie for wildlife use, but it is safe enough for domestic animals as well. 3 figures

  20. Mine flooding and barrier pillar hydrology in the Pittsburgh basin

    International Nuclear Information System (INIS)

    Leavitt, B.R.

    1999-01-01

    Pennsylvania began requiring barrier pillars between mines as early as 1930. The Ashley formula, resulting from a early commission on the problem, requires 20 feet of coal plus a thickness of coal equal to four times the seam height plus an additional thickness of coal equal to one tenth of the overburden thickness, or the maximum potential hydraulic head. For a 6-foot thick coal seam under 400 feet of cover, the barrier would be 20+24+40=84 feet. The Ashley formula is intended to protect coal miners from a catastrophic failure of a barrier pillar which has a high head of water impounded behind it. The paper gives several examples of flooded and unflooded mines and the performance of their barrier pillars with respect to acid mine drainage. It is concluded that for all practical purposes, barrier pillars designed with the Ashley formula are able to hydrologically isolate mines from one another. This hydrologic isolation promotes the inundation of closed mines. Inundation effectively stops acid formation, thus, fully inundated mines do not represent a perpetual source of acid mine drainage. Infiltrating ground water improves the mine water chemistry resulting in a net alkaline discharge which has greatly lowered iron concentrations. The best locations for acid mine drainage treatment plants is at the lowest surface elevation above the mine with mine flooded to near that elevation

  1. Lignite mining and electricity generation in Poland: The current state and future prospects

    International Nuclear Information System (INIS)

    Widera, Marek; Kasztelewicz, Zbigniew; Ptak, Miranda

    2016-01-01

    This opinion paper presents the current state and future scenarios of Polish lignite mining. For many years, over 1/3 of domestic electricity, that is about 53–55 TWh, has been generated by lignite-fired power plants. Currently, with 63–66 million tons of extraction, Poland is the fourth lignite producer worldwide and the second in the European Union. There are three possible scenarios for the development of lignite mining in Poland by 2050. Unfortunately, despite the huge lignite resources, amounting to more than 23.5 billion tons, and great potential of the mining industry, the future of Polish lignite mining does not look optimistic from the economic point of view. This is associated with social and environmental problems, including the European Union's climate and energy policy. However, this may change in the event of a global economic crisis and unstable geopolitical conditions. Therefore, a new energy doctrine for Poland at least by 2050 is urgently needed. - Highlights: •Poland is one of the leaders in lignite production in the European Union. •Energy policy in Poland assumes a key role of lignite in energy mix. •Almost one-third of Polish electricity is currently generated from lignite. •For Polish lignite mining exist pessimistic, realistic and optimistic scenarios. •Extraction of lignite in Poland will gradually decrease in the coming decades.

  2. Lignite industry in Greece within a world context: Mining, energy supply and environment

    International Nuclear Information System (INIS)

    Kavouridis, Konstantinos

    2008-01-01

    Today coal covers 38% of global production and roughly 30% of the EU-25 power output. In 2005 domestic lignite with a share of 60.5% in power generation and accounting about 30% of primary energy consumption is currently the most important indigenous fuel of Greece. Greece, mining 70 Mt annually, is the second lignite producer in the EU and fourth in the world. Approximately 97% of the lignite used to supply the existing lignite-fired power plants of Greece is mined by Public Power Corporation S.A. (PPC). Lignite as the base load fuel gives a competitive strength in PPC's and Greece's fuel mix. Due to lignite consumer prices in Greece are significantly below those in other comparable markets in EU-15. Extraction of lignite has a very long tradition. Significant achievements and large experience which has been gained during many years of mining operations place Greek lignite-mining industry in the leading position in Europe. The paper presents current state of Greek lignite industry, including operating mines, volume of production and other important production indicators as well as improvements in labor productivity and good results in industrial safety. The future of coal and specifically of Greek lignite will be crucially determined by environmentally compatible, i.e. low-CO 2 generation of electricity. Investment in modernization and renewal of the power plant fleet are the key to securing electricity supply and progress in preventing climate change

  3. Rib-pillar mining at Sigma Colliery

    Energy Technology Data Exchange (ETDEWEB)

    De Beer, J J.S.; Hunter, F; Neethling, A F [Sigma Colliery, Sasolburg (South Africa)

    1991-06-01

    The paper describes the rib-pillar extraction method now used at Sigma Colliery in the Orange Free State. In this method, access roadways (with a high safety factor) are developed into a block of coal suitable for total extraction; pillars that have a low safety factor are then formed and extracted immediately. The method, together with the current practices of labour management, has resulted in better utilization of the coal resources and capital, increased production and labour productivity, and improved safety. 11 figs.

  4. Bucket wheel excavator performances at Neyveli lignite mine

    Energy Technology Data Exchange (ETDEWEB)

    Kumaraswamy, S; Mozumdar, B K

    1987-03-01

    Bucket-wheel excavators have been in use at the Neyveli Lignite Mine in the State of Tamil Nadu, India, since the early nineteen-sixties. The mining environment has been particularly harsh for BWE application. The adverse influencing factors are the hardness of the over-burden formation, high abrasivity of rock and artesian ground water conditions. In this paper, the performances of the BWEs at Neyveli have been statistically analysed to determine the effects of physico-mechanical properties of overburden, blasting and rainfall on machine productivity, availability, wear-and-tear of bucket teeth, power consumption, production efficiency and cost of mining. An empirical relationship between the production efficiency, defined as the ratio of actual production rate to the theoretical one, and the bench height and width, height of slices, specific cutting resistance of the overburden material and its clay content, consumption of explosives, and conveyor length has been established.

  5. Report on the survey of abandoned uraniferous lignite mines in southwestern North Dakota

    International Nuclear Information System (INIS)

    Lyon, R.J.; Prochaska, D.; Burgess, J.L.; Patrick, D.

    1986-03-01

    A radiation survey was conducted in October 1983 as part of the proposed reclamation plan of abandoned uraniferous lignite mines in southwestern North Dakota. The survey was made to determine the extent of contamination caused by mining operations in the 1960's. Radiation measurements were made and soil samples were taken at approximately 300 locations around six mine sites comprising eleven lignite mine pits. Toxic element analysis was also done on 50 of the soil samples

  6. Fold catastrophe model of dynamic pillar failure in asymmetric mining

    Energy Technology Data Exchange (ETDEWEB)

    Yue Pan; Ai-wu Li; Yun-song Qi [Qingdao Technological University, Qingdao (China). College of Civil Engineering

    2009-01-15

    A rock burst disaster not only destroys the pit facilities and results in economic loss but it also threatens the life of the miners. Pillar rock burst has a higher frequency of occurrence in the pit compared to other kinds of rock burst. Understanding the cause, magnitude and prevention of pillar rock burst is a significant undertaking. Equations describing the bending moment and displacement of the rock beam in asymmetric mining have been deduced for simplified asymmetric beam-pillar systems. Using the symbolic operation software MAPLE 9.5 a catastrophe model of the dynamic failure of an asymmetric rock-beam pillar system has been established. The differential form of the total potential function deduced from the law of conservation of energy was used for this deduction. The critical conditions and the initial and final positions of the pillar during failure have been given in analytical form. The amount of elastic energy released by the rock beam at the instant of failure is determined as well. A diagrammatic form showing the pillar failure was plotted using MATLAB software. This graph contains a wealth of information and is important for understanding the behavior during each deformation phase of the rock-beam pillar system. The graphic also aids in distinguishing the equivalent stiffness of the rock beam in different directions. 11 refs., 8 figs.

  7. Appraisal of Hydrologic Information Needed in Anticipation of Lignite Mining in Lauderdale County, Tennessee

    Science.gov (United States)

    Parks, William Scott

    1981-01-01

    Lignite in western Tennessee occurs as lenses or beds at various stratigraphic horizons in the Coastal Plain sediments of Late Cretaceous and Tertiary age. The occurrence of this lignite has been known for many decades, but not until the energy crisis was it considered an important energy resource. In recent years, several energy companies have conducted extensive exploration programs in western Tennessee, and tremendous reserves of lignite have been found. From available information, Lauderdale County was selected as one of the counties where strip-mining of lignite will most likely occur. Lignite in this county occurs in the Jackson and Cockfield Formations, undivided, of Tertiary age. The hydrology of the county is known only from regional studies and the collection of some site-specific data. Therefore, in anticipation of the future mining of lignite, a plan is needed for obtaining hydrologic and geologic information to adequately define the hydrologic system before mining begins and to monitor the effects of strip-mining once it is begun. For this planning effort, available hydrologic, geologic, land use, and associated data were located and compiled; a summary description of the surface and shallow subsurface hydrologic system was prepared: the need for additional baseline hydrologic information was outlined; and plans to monitor the effects of strip-mining were proposed. This planning approach, although limited to a county area, has transferability to other Coastal Plain areas under consideration for strip-mining of lignite.

  8. Sustainable lignite mining and utilization. Developments in the Rhenish lignite-mining area; Nachhaltige Braunkohlegewinnung und -nutzung. Entwicklung im Rheinischen Revier

    Energy Technology Data Exchange (ETDEWEB)

    Gaertner, Dieter [RWE Power AG, Bergheim (Germany). Opencast Mines Div.

    2012-03-15

    Lignite is an essential module in the Rhenish mining area's economic power. Mining in a densely populated region like the Rhineland calls for keeping an eye equally on people, the environment and industry now and in the future. By considering all concerns and ensuring transparency in our approach to people, we have succeeded in obtaining public acceptance also for large-scale projects in an environment that is not always easy in Germany. RWE Power plans to use lignite in power generation and in upgrading operations for many decades to come, so that the company is systematically implementing the power-plant renewal programme with is planning for BoAplus as highly efficient next-generation lignite-based power plants. Research on CO{sub 2} utilization, flexibilization, energy storage and alternative uses of lignite are as much features of RWE Power's future-proof alignment in the Rhenish mining area as are further innovations in the opencast mines. Core aspects here include further automation in the deployment of main mine equipment, closely dovetailed with innovations in other operating units. Parallel restructuring of the operating units and the Lignite Approvals area are underpinning these measures. Innovations and their translation into technical progress will ensure the success of a measured energy turnaround both in Germany and throughout Europe. However, this requires dependable political conditions, so that an engineering spirit can go on being transformed into entrepreneurial action. (orig.)

  9. Pillarization

    NARCIS (Netherlands)

    Maussen, M.; Stone, J.; Dennis, R.M.; Rizova, P.S.; Smith, A.D.; Hou, X.

    2016-01-01

    Pillarization describes a society as divided into a number of "pillars," being compartments standing for the networks of organizations belonging to religious and ideological subcultures. Typically the associations cover a broad range of societal domains (education, media, political parties). The

  10. Sustainable lignite mining and utilization. Developments in the Rhenish lignite-mining area; Nachhaltige Braunkohlegewinnung und -nutzung. Entwicklung im Rheinischen Revier

    Energy Technology Data Exchange (ETDEWEB)

    Gaertner, Dieter [RWE Power AG, Bergheim (Germany). Sparte Tagebaue

    2012-09-15

    Lignite is an essential module in the Rhenish mining area's economic power. Mini ng in a densely populated region like the Rhineland calls for keeping an eye equ ally on people, the environment and industry now and in the future. By considering all concerns and ensuring transparency in our approach to people, we have succeeded in obtaining public acceptance also for large-scale projects in an environment that is not always easy in Germany. RWE Power plans to use lignite in powe r generation and in upgrading operations for many decades to come, so that the company is systematically implementing the power-plant renewal programme with is planning for BoAplus as highly efficient next-generation lignite-based power plants. Research on CO{sub 2} utilization, flexibilization, energy storage and alternative uses of lignite are as much features of RWE Power's future-proof alignment in the Rhenish mining area as are further innovations in the opencast mines. Core aspects here include further automation in the deployment of main mine equipment, closely dovetailed with innovations in other operating units. Parallel restructuring of the operating units and the Lignite Approvals area are underpinning these measures. Innovations and their translation into technical progress will ensure the success of a measured energy turnaround both in Germany and throughout Europe. However, this requires dependable political conditions, so that an engineering spirit can go on being transformed into entrepreneurial action. (orig.)

  11. Foreseen development of mining of lignite; Przewidywany rozwoj gornictwa wegla brunatnego

    Energy Technology Data Exchange (ETDEWEB)

    Kozlowski, Z. [Wroclaw University of Technology, Wroclaw (Poland). Dept. of Geo-engineering, Mining and Geology

    2004-07-01

    The future of activity in Poland's lignite sector will be determined by the demand for this fuel, which will in turn result from mining possibilities and economic competitiveness of the fuel in relation to other sources of electrical energy. The paper discusses all these factors and presents a framework programme for the development of Poland's lignite sector until 2040 (in detail) and further ahead to 2075, called the 'Agreement of manufacturers of lignite'. 4 refs., 5 tabs.

  12. Numerical Analysis on Failure Modes and Mechanisms of Mine Pillars under Shear Loading

    Directory of Open Access Journals (Sweden)

    Tianhui Ma

    2016-01-01

    Full Text Available Severe damage occurs frequently in mine pillars subjected to shear stresses. The empirical design charts or formulas for mine pillars are not applicable to orebodies under shear. In this paper, the failure process of pillars under shear stresses was investigated by numerical simulations using the rock failure process analysis (RFPA 2D software. The numerical simulation results indicate that the strength of mine pillars and the corresponding failure mode vary with different width-to-height ratios and dip angles. With increasing dip angle, stress concentration first occurs at the intersection between the pillar and the roof, leading to formation of microcracks. Damage gradually develops from the surface to the core of the pillar. The damage process is tracked with acoustic emission monitoring. The study in this paper can provide an effective means for understanding the failure mechanism, planning, and design of mine pillars.

  13. Distribution and correlation of the natural radionuclides in a coal mine of the West Macedonia Lignite Center (Greece).

    Science.gov (United States)

    Tsikritzis, L I; Fotakis, M; Tzimkas, N; Kolovos, N; Tsikritzi, R

    2008-02-01

    The distribution and correlation of six natural nuclides in the West Macedonia Lignite Center, Northern Greece were studied. Fifty-five samples of lignite, aged from 1.8 to 5 million years, and corresponding steriles, beds of marls, clays and sands alternating with the lignite, were collected perpendicular to the mine benches and measured spectroscopically. The mean concentrations of (238)U and (226)Ra in lignites were found to be higher than that in steriles since these nuclides are associated with the organic material of lignite, whereas (238)U/(226)Ra equilibrium was not observed in either lignites or steriles. Finally, the ratio (226)Ra/(228)Ra in lignites was approximately double of that in steriles, confirming the affinity of the (238)U series with the coal matrix in contrast to the (232)Th series. No correlation was found between radionuclide concentrations and the depth of the sample, nor with the ash content of lignite.

  14. Pessimistic Determination of Mechanical Conditions and Micro/macroeconomic Evaluation of Mine Pillar Replacement

    Science.gov (United States)

    Chen, Qingfa; Zhao, Fuyu

    2017-12-01

    Numerous pillars are left after mining of underground mineral resources using the open stope method or after the first step of the partial filling method. The mineral recovery rate can, however, be improved by replacement recovery of pillars. In the present study, the relationships among the pillar type, minimum pillar width, and micro/macroeconomic factors were investigated from two perspectives, namely mechanical stability and micro/macroeconomic benefit. Based on the mechanical stability formulas for ore and artificial pillars, the minimum width for a specific pillar type was determined using a pessimistic criterion. The microeconomic benefit c of setting an ore pillar, the microeconomic benefit w of artificial pillar replacement, and the economic net present value (ENPV) of the replacement process were calculated. The values of c and w were compared with respect to ENPV, based on which the appropriate pillar type and economical benefit were determined.

  15. Distribution of vesicular-arbuscular mycorrhizal fungi in coal, lignite and calcite mine spoils of India

    Energy Technology Data Exchange (ETDEWEB)

    Ganesan, V.; Ragupathy, S.; Parthipan, B.; Rani, D.B.R.; Mahadevan, A.

    1991-12-31

    Vesicular-arbuscular mycorhizzal (VAM) status was assessed for coal, lignite and calcite mine spoils. The three study sites were: The Kothagudem coal field in the south central region where waste materials are piled 1 to 2 m high on the soil surface. Samples were collected from plants growing on the waste. Neyveli, on the southeastern coast, is a lignite coal mine where the spoil is piled 70 to 100 m high on the soil surface. Samples were collected from recently revegetated mine spoil and from 25 year old revegetated sites. The calcite mine at Thazhaiyuthu in the south where the spoil is piled up 2 to 3 m on the soil surface. Samples were collected from 4 to 7 year old reclaimed sites. The wastes generally supported different plant species. The level of VAM infection of plants was markedly different in each mine spoil, with the maximum infection in the coal and calcite spoils, and the least in the lignite spoil. There was more infection in the 25 year old lignite spoil than in the newly revegetated spoil. There were different VAM species in each spoil, and no one species was present in all of the samples. The authors conclude that one of the factors leading to the differences between spoils is the amount of topsoil contained in the spoil (least in the lignite spoils which are very deep). The other is age of the spoils. Unfortunately the authors concluded that the best approach is to enrich the spoils with VAM rather than salvaging and replacing topsoil

  16. The Effect of Mining Activity on the Surface in the Safety Shaft Pillar Area of Mayrau Mine

    Czech Academy of Sciences Publication Activity Database

    Živor, Roman; Klos, Pavel; Pechoč, Jiří; Brož, Milan

    M-24(340) (2002), s. 227-235 ISSN 0138-015X. [Polish-Czech-Slovakian Symposium on Mining Geophysics /28./. Niedzica, 11.06.2001-13.06.2001] R&D Projects: GA AV ČR IBS3086005 Institutional research plan: CEZ:AV0Z3046908 Keywords : shaft pillar * mining * surface subsidence Subject RIV: DH - Mining, incl. Coal Mining

  17. Determination of optimal environmental policy for reclamation of land unearthed in lignite mines - Strategy and tactics

    Science.gov (United States)

    Batzias, Dimitris F.; Pollalis, Yannis A.

    2012-12-01

    In this paper, optimal environmental policy for reclamation of land unearthed in lignite mines is defined as a strategic target. The tactics concerning the achievement of this target, includes estimation of optimal time lag between each lignite site (which is a segment of the whole lignite field) complete exploitation and its reclamation. Subsidizing of reclamation has been determined as a function of this time lag and relevant implementation is presented for parameter values valid for the Greek economy. We proved that the methodology we have developed gives reasonable quantitative results within the norms imposed by legislation. Moreover, the interconnection between strategy and tactics becomes evident, since the former causes the latter by deduction and the latter revises the former by induction in the time course of land reclamation.

  18. Securing the future of the Lusatian lignite mining; Zukunftssicherung im Lausitzer Revier

    Energy Technology Data Exchange (ETDEWEB)

    Klocek, Gert [Vattenfall Europe Mining AG, Cottbus (Germany). Bergbauplanung; Ketzmer, Wolfgang [Vattenfall Europe Mining AG, Cottbus (Germany). Grunddaten und Bergtechnik

    2014-11-01

    In the course of securing the future of the Lusatian lignite mining, the company has initiated several measures and activities. Thus with large-scale projects such as relocating the operating and surface facilities of the Welzow-Sued opencast mine uninterrupted long-term mining advance is ensured. The company's lignite-fired power plants with their project ''FlexGen'', to further increased flexibility, enhances their position to master of the challenges of ''Energiewende''. The political and societal framework for this complex development is in line with the climate and energy programmes or strategies of the Free State of Saxony and the federal state of Brandenburg.

  19. Sustainable development of lignite production on open cast mines in Serbia

    Energy Technology Data Exchange (ETDEWEB)

    Darko Danicic; Slobodan Mitrovic; Vladimir Pavlovic; Sava Kovacev [Kolubara Metal, Vreoci (Serbia)

    2009-09-15

    Currently operated coalmines in Serbia (Kolubara and Kostolac) have production around 36 million tons of lignite, and over 108 million m{sup 3} of overburden. Consequently, sustainability of lignite production requires cost reduction and environmental protection, as well as capacity increase. In order to rationalise, and increase efficiency of Serbian lignite mines, it is necessary to focus the activities on major issues shown within the triangle of energy policy objectives (security of supply, competitive prices and environmental protection). Production process optimisation singled out several special programs. Equipment revitalization and modernization is necessary taking into account that majority of the currently operated machinery has a life up to 25 years. Production process automation would enable high level of technical operation in the field of open cast mines management. Lack of coal quality uniformity is the permanent problem resulting by great amounts of coal reserves to be used uneconomically. Planning and training at all levels and finally cooperative software for business procedures and work order management. The measures suggested are a key precondition for maintaining competitive position of lignite production on international level. 7 refs., 5 figs., 1 tab.

  20. Petrological, geochemical and isotopic characteristics of lignite and calcified lignite from mining area Pesje, Velenje Basin, Slovenia

    Science.gov (United States)

    Vrabec, Mirijam; Markič, Miloš; Vrabec, Marko; Jaćimović, Radojko; Kanduč, Tjaša

    2014-05-01

    Lignite (organic rich) and calcified lignite (inorganic rich) samples from excavation field -50c mining area Pesje, Velenje Basin, Slovenia were investigated. During geological and structural mapping lignite and calcified lignite samples were systematically taken for determination of their petrological, geochemical and isotopic characteristics. Lignite is composed of fine detritical gelified matrix. At least five different types of calcified lignite were recognized forming laminations, calcifications after wood, petrified wood and complete replacements of lignite with carbonate. All measured parameters so far indicate geochemical processes during sedimentation of the Velenej Basin. After macroscopic description samples were split to organic and inorganic component (Ward, 1984) and powdered in an agate mortar for geochemical and isotopic analyses. Major and trace elements (As, B, Ba, Cd, Co, Cr, Cu, Hg, Mn, Mo, Sb, Se, Th, U, Zn) in these samples were determined by instrumental neutron activation analysis (INAA) using k-0 standardization method (Jaćimović et al, 2002). The isotopic composition of carbon and nitrogen was determined using a Europa 20-20 continuous flow IRMS ANCA-SL preparation module. A 1 mg amount of a sample was weighed in a tin capsule for carbon and 10 mg for nitrogen analysis. Samples for carbon analyses were pretreated with 1 M HCl to remove carbonates. Carbonate samples from carbonate-rich strata and calcified xylite were first roasted at 450 deg C (Krantz et al., 1987). Three miligrams of carbonate sample was transformed into CO2 by reaction with anhydrous H3PO4 at 55 deg C under vacuum (McCrea, 1950) and measured with GV 2003 isotope ratio mass spectrometer. Measured isotopic composition of oxygen as VPDB values was recalculated to the VSMOW reference standard to enable the comparison with data from other coal basins. SEM/EDXS of carbonate rich sediments was performed with JEOL JSM 5800 electron microanalyzer scanning electron microscope

  1. Estimation of spatial variability of lignite mine dumping ground soil properties using CPTu results

    Directory of Open Access Journals (Sweden)

    Bagińska Irena

    2016-03-01

    Full Text Available The paper deals with application of CPTu test results for the probabilistic modeling of dumping grounds. The statistical measures use results from 42 CPT test points located in the lignite mine dumping ground from the region of Central Europe. Both the tip resistance qc as well as local friction fs are tested. Based on the mean values and standard deviations of measured quantities the specific zones in the dumping site profile are distinguished. For three main zones standard deviations of linearly de-trended functions, distributions of normalized de-trended values for qc and fs are examined. Also the vertical scales of fluctuation for both measured quantities are estimated. The obtained result shows that lignite mine dumping site can be successfully described with the Random Field Theory. Additional use of fs values introduces supplementary statistical information.

  2. Late Neogene leaf assemblage from Bełchatów Lignite Mine (central Poland

    Directory of Open Access Journals (Sweden)

    Worobiec Grzegorz

    2014-12-01

    Full Text Available Leaf macroremains collected in the Bełchatów Lignite Mine (central Poland were investigated. The fossil assemblage consists of leaves of Acer, Betula, Carpinus, Dicotylophyllum, Fagus, ?Magnolia, “Parrotia”, Pinus, Quercus, and Zelkova. Mesophytic (zonal elements dominate, with admixture of riparian (azonal leaf taxa. The floristic composition points to late Neogene (late Miocene to late Pliocene age and suggests favourable temperate climate with mild winters.

  3. Production scheduling of a lignite mine under quality and reserves uncertainty

    International Nuclear Information System (INIS)

    Galetakis, Michael; Roumpos, Christos; Alevizos, George; Vamvuka, Despina

    2011-01-01

    The effect of uncertainty sources to the stochastic optimization of the combined project of a new surface lignite mine exploitation and power plant operation for electricity generation is investigated. Major sources of uncertainty that were considered are the reserves and the quality of the lignite. Since probability distribution functions for these uncertainties were estimated during the detailed exploration phase of the deposit, the overall goal is then to determine the optimal capacity of the power plant and consequently the optimal production rate of the mine over the time. The optimization objective that was selected is the maximization of the net present value of the project. Emphasis is placed on the sensitivity analysis for the investigation of the effect of quality and reserves uncertainty on project optimization, on the mathematical formulation of risk attitude strategy and on increasing the efficiency of the optimization process by creating a limited set of feasible solutions applying empirical rules. The developed methodology was applied for the determination of the optimal annual production rate of a new surface lignite mine in the area of Ptolemais–Amynteon in Northern Greece. - Highlights: ► Quality and reserves uncertainty affects considerably the production scheduling. ► Stochastic optimization is greatly accelerated by incorporating Taylor's rule. ► Decisions can be made considering different risk level attitudes.

  4. Reprint of: Production scheduling of a lignite mine under quality and reserves uncertainty

    International Nuclear Information System (INIS)

    Galetakis, Michael; Roumpos, Christos; Alevizos, George; Vamvuka, Despina

    2012-01-01

    The effect of uncertainty sources to the stochastic optimization of the combined project of a new surface lignite mine exploitation and power plant operation for electricity generation is investigated. Major sources of uncertainty that were considered are the reserves and the quality of the lignite. Since probability distribution functions for these uncertainties were estimated during the detailed exploration phase of the deposit, the overall goal is then to determine the optimal capacity of the power plant and consequently the optimal production rate of the mine over the time. The optimization objective that was selected is the maximization of the net present value of the project. Emphasis is placed on the sensitivity analysis for the investigation of the effect of quality and reserves uncertainty on project optimization, on the mathematical formulation of risk attitude strategy and on increasing the efficiency of the optimization process by creating a limited set of feasible solutions applying empirical rules. The developed methodology was applied for the determination of the optimal annual production rate of a new surface lignite mine in the area of Ptolemais–Amynteon in Northern Greece. - Highlights: ► Quality and reserves uncertainty affects considerably the production scheduling. ► Stochastic optimization is greatly accelerated by incorporating Taylor's rule. ► Decisions can be made considering different risk level attitudes.

  5. Neyveli lignite - a status overview

    Energy Technology Data Exchange (ETDEWEB)

    Tandon, G L

    1984-11-14

    The lignite mines of the Neyveli Lignite Corporation in Tamil Nadu in India are described: characteristics of the deposit; choice of mining method (surface mining); groundwater control; storm water control; overburden removal; mining equipment (bucket wheel excavators, belt conveyors and spreaders); generation of electric power; production of fertilizer; production of lignite briquettes and tar products. A second mine and thermal power plant are planned.

  6. Condition-Based Conveyor Belt Replacement Strategy in Lignite Mines with Random Belt Deterioration

    Science.gov (United States)

    Blazej, Ryszard; Jurdziak, Leszek

    2017-12-01

    In Polish lignite surface mines, condition-based belt replacement strategies are applied in order to assure profitable refurbishment of worn out belts performed by external firms specializing in belt maintenance. In two of three lignite mines, staff asses belt condition subjectively during visual inspections. Only one mine applies specialized diagnostic device (HRDS) allowing objective magnetic evaluation of belt core condition in order to choose the most profitable moment for the dismantling of worn out belt segments from conveyors and sending them to the maintenance firm which provides their refurbishment. This article describes the advantages of a new diagnostic device called DiagBelt. It was developed at the Faculty of Geoengineering, Mining and Geology, Wroclaw University of Science and Technology. Economic gains from its application are calculated for the lignite mine and for the belt maintenance firm, taking into account random life (durability) of new and reconditioned belts (after the 1st and the 2nd refurbishment). Recursive calculations for following years allow the estimation of the length and costs of replaced, reconditioned and purchased belts on an annual basis, while the use of the Monte Carlo method allows the estimation of their variability caused by random deterioration of belts. Savings are obtained due to better selection of moments (times) for the replacement of belt segments and die to the possibility to qualify worn out belts for refurbishment without the need to remove their covers. In effect, increased belt durability and lowered share of waste belts (which were not qualified for reconditioning) create savings which can quickly cover expenditures on new diagnostic tools and regular belt inspections in the mine.

  7. Land movement monitoring at the Mavropigi lignite mine using spaceborne D-InSAR

    Science.gov (United States)

    Papadaki, Eirini; Tripolitsiotis, Achilleas; Steiakakis, Chrysanthos; Agioutantis, Zacharias; Mertikas, Stelios; Partsinevelos, Panagiotis; Schilizzi, Pavlos

    2013-08-01

    This paper examines the capability of remote sensing radar interferometry to monitor land movements, as it varies with time, in areas close to open pit lignite mines. The study area is the "Mavropigi" lignite mine in Ptolemais, Northern Greece; whose continuous operation is of vital importance to the electric power supply of Greece. The mine is presently 100-120m deep while horizontal and vertical movements have been measured in the vicinity of the pit. Within the mine, ground geodetic monitoring has revealed an average rate of movement amounting to 10-20mm/day at the southeast slopes. In this work, differential interferometry (DInSAR), using 19 Synthetic Aperture Radar (SAR) images of ALOS satellite, has been applied to monitor progression of land movement caused my mining within the greater area of "Mavropigi" region. The results of this work show that DInSAR can be used effectively to capture ground movement information, well before signs of movements can be observed visually in the form of imminent fissures and tension cracks. The advantage of remote sensing interferometry is that it can be applied even in inaccessible areas where monitoring with ground equipment is either impossible or of high-cost (large areas).

  8. Mining a coal seam with caving in a protective pillar of a mine shaft. [Poland

    Energy Technology Data Exchange (ETDEWEB)

    Szymura, G; Dilling, R; Kowalski, A

    1984-01-01

    Mining the 620 seam is evaluated (from 1.5 to 1.7 m thick at a depth of 468 m in the protective pillar of the upcast mine shaft used for ventilation, manriding and transport of materials in the Pstrowski mine in Upper Silesia). The shaft is 496 m deep, has a diameter of 3.5 m and its liners are made of bricks. Ground subsidence caused by underground mining influenced: the head frame above the shaft, residential buildings, a church, railway tracks and a river bed. A system of shortwall mining with caving was used. Deformation of shaft liners was reduced by advanced cutting of a coal block 30x30 m around the shaft. A system of timber cribbings and yielding elements was used. Design of support systems used around the shaft is shown in 3 schemes. Shaft deformation was within permissible limits. The maximum ground subsidence (0.95 m) occurred in the river area. Ground subsidence in the area of the church ranged from 0.75 to 0.81 m and in the head frame area 0.84 m. Accuracy of ground subsidence and shaft deformation forecasting was high. 4 references.

  9. 30 CFR 75.380 - Escapeways; bituminous and lignite mines.

    Science.gov (United States)

    2010-07-01

    ... sections in contact to form two diamond shapes. The cones must be placed within reach of the lifeline. (B... surface fires, fumes, smoke, and flood water from entering the mine. (f) Primary escapeway. (1) One.... (iv) Water pumps, except— (A) Water pumps necessary to maintain the escapeway in safe, travelable...

  10. Local community opinions regarding the socio-environmental aspects of lignite surface mining: Experiences from central Poland

    International Nuclear Information System (INIS)

    Badera, Jarosław; Kocoń, Paweł

    2014-01-01

    Surface lignite mining covers large areas and usually generates social conflicts which pose one of several energy security threats to certain states. Therefore, defining the social conditions determines the success of a mining project. Two communes were chosen for a public opinion study: Kleszczów, where the Bełchatów mine is located, and Złoczew, where a lignite deposit will soon be developed. The analysis shows, as opposed to other areas in Poland that have been projected for development, that both local communities are characterised by a high level of acceptance for lignite mining. In both cases, awareness about the profits was stronger than anxiety about the investment's negative effects. However, most inhabitants could not assess the mining company's diligence concerning its responsibility for mining damages as well as the diligence of external experts assessing the environmental impacts of excavation. Most respondents also could not assess if the legal regulations of public participation in the decision process were sufficient, but the negative opinions outweighed the positive ones. From the perspective of the energy policy, dialogue-type social communication is needed for every case of a new energy-mining project. Research on local public opinion should be the first step to opening up a social debate. - Highlights: • Lignite mining can generate social conflicts, which may threaten energy security. • Examined communes are characterised by a high level of acceptance for lignite mining. • Inhabitants cannot assess if the legal regulations of mining activity are sufficient. • From the perspective of the energy policy, broader social communication is needed. • Research on the public opinion should be the first step to open up a social debate

  11. Rock mechanics of crown pillars between cut-and-fill stopes at the Mount Isa mine

    Energy Technology Data Exchange (ETDEWEB)

    Lee, M. F.; Bridges, M. C.

    1980-05-15

    At both levels, the leading stopes experienced bad ground conditions due to high stresses in the stope's backs when the crown pillars were about 35 m high. At 9 level, cut-and-fill mining stopped and most of the crown pillars were extracted by a slot-and-massfire method. At 11 level, cut-and-fill mining continued. Shear displacement along bedding planes began within and around the crown pillars of the leading stopes at 11 level, and spread through other crown pillars and to the hangingwall of the stoping system. Destressing and good ground conditions occurred where shear occurred, with further concentrations of stress in other areas. Crown pillars are being extracted to leave minimal 1:2 height to width diaphragms under the stopes above. Ground behavior of the 11 level crown pillars was investigated by observation, stress measurement, regional surveying of displacement and finite element models. An explanation of the ground behavior has evolved from this work. Bedding planes with an estimated angle of sliding friction of 10/sup 0/ were the main factor determining the behavior of this area.

  12. Diagnostic measurements on the great machines conditions of lignite surface mines

    Energy Technology Data Exchange (ETDEWEB)

    Helebrant, F.; Jurman, J.; Fries, J. [Technical University of Ostrava, Ostrava-Poruba (Czech Republic)

    2005-07-01

    An analysis of the diagnosis of loading and service dependability of a rail-mounted excavator used in surface lignite mining is described. Wheel power vibrations in electric motor bearings and electric motor input bearings to the gearbox were measured in situ, in horizontal, vertical, and axial directions. The data were analyzed using a mathematical relationship. The results are presented in a loading diagram that shows the deterioration and the acceptable lower bound of machine conditions over time. Work is continuing. 5 refs., 1 fig.

  13. An ecosystem approach to evaluate restoration measures in the lignite mining district of Lusatia/Germany

    Science.gov (United States)

    Schaaf, Wolfgang

    2015-04-01

    Lignite mining in Lusatia has a history of over 100 years. Open-cast mining directly affected an area of 1000 km2. Since 20 years we established an ecosystem oriented approach to evaluate the development and site characteristics of post-mining areas mainly restored for agricultural and silvicultural land use. Water and element budgets of afforested sites were studied under different geochemical settings in a chronosequence approach (Schaaf 2001), as well as the effect of soil amendments like sewage sludge or compost in restoration (Schaaf & Hüttl 2006). Since 10 years we also study the development of natural site regeneration in the constructed catchment Chicken Creek at the watershed scale (Schaaf et al. 2011, 2013). One of the striking characteristics of post-mining sites is a very large small-scale soil heterogeneity that has to be taken into account with respect to soil forming processes and element cycling. Results from these studies in combination with smaller-scale process studies enable to evaluate the long-term effect of restoration measures and adapted land use options. In addition, it is crucial to compare these results with data from undisturbed, i.e. non-mined sites. Schaaf, W., 2001: What can element budgets of false-time series tell us about ecosystem development on post-lignite mining sites? Ecological Engineering 17, 241-252. Schaaf, W. and Hüttl, R. F., 2006: Direct and indirect effects of soil pollution by lignite mining. Water, Air and Soil Pollution - Focus 6, 253-264. Schaaf, W., Bens, O., Fischer, A., Gerke, H.H., Gerwin, W., Grünewald, U., Holländer, H.M., Kögel-Knabner, I., Mutz, M., Schloter, M., Schulin, R., Veste, M., Winter, S. & Hüttl, R.F., 2011: Patterns and processes of initial terrestrial-ecosystem development. Journal of Plant Nutrition and Soil Science, 174, 229-239. Schaaf, W., Elmer, M., Fischer, A., Gerwin, W., Nenov, R., Pretsch, H. and Zaplate, M.K., 2013: Feedbacks between vegetation, surface structures and hydrology

  14. Isolation and identification of a Candida digboiensis strain from an extreme acid mine drainage of the Lignite Mine, Gujarat.

    Science.gov (United States)

    Patel, Mitesh J; Tipre, Devayani R; Dave, Shailesh R

    2009-12-01

    An extremely acidic mine drainage (AMD) water sample was collected in 1998 and 2008 from Panandhro lignite mine, Gujarat, India. The yeast isolated from this sample was identified using mini API identification system, as a member of genus Candida. The major cellular fatty acids detected by FAME from the isolate are C(16:0) and C(18:2) (cis 9,12)/C(18:0alpha) as 25.23 and 19.5%, respectively. The isolate was identified as Candida digboiensis by 18S rRNA gene sequence analysis and designated as Candida digboiensis SRDyeast1. Phylogenetic analysis using D1/D2 variable domains showed that the closest relative of this strain is Candida blankii with 3% divergence. This organism has been reported for the first time from the lignite mine AMD sample, and for cellular fatty acid analysis. This yeast is able to survive in the AMD sample preserved at 10-42 degrees C temperature since last 10 years along with iron oxidizing microorganisms. It can grow in the presence of 40% glucose, 10% NaCl and in the pH range of 1 to 10. The isolate is capable of producing enzymes like protease and lipase. This isolate differs from the type strain Candida digboiensis in as many as six physiological and metabolic characteristics.

  15. Empirical approach for designing of support system in mechanized coal pillar mining

    Energy Technology Data Exchange (ETDEWEB)

    Kushwaha, A.; Singh, S.K.; Tewari, S.; Sinha, A. [Central Institute of Mining & Fuel Research, Dhanbad (India)

    2010-10-15

    Mechanized room-and-pillar system of coal pillar mining using side dump loading machine or load haul dumper machine, or by continuous miner, is the presently most dominant under ground method of extraction in India. Under this method of extraction, strata control is a major problem affecting safety and productivity of the mine. As per existing Director General of Mine Safety guidelines, systematic support rules must be followed at the depillaring faces irrespective of immediate roof rock type and competency. Therefore, there is a high chance that sometimes these systematic support rules give unnecessarily high support, or sometimes inadequate support, which may lead to roof failure at the face. As a result, there is a big loss of life and material including coal in terms of left-outribs/stooks and other associated mining equipment deployed at the faces. Therefore, in the present paper, authors attempted to develop generalized empirical equations for estimating the required support load density at different places of the face based on geotechnical parameters of the mine and physico-mechanical properties of the immediate roof rocks for designing of support system during mechanized coal pillar mining.

  16. Planning maximum extraction of a safety pillar in the Most surface mine

    Energy Technology Data Exchange (ETDEWEB)

    Helis, P; Hess, L; Kubiznak, K [SHR - Banske Projekty, Teplice (Czechoslovakia)

    1990-11-01

    Discusses planned coal surface mining in the Most mine in the area of the Hnevin safety pillar with coal reserves amounting to about 7.5 Mt. The following aspects are evaluated: coal reserves and their distribution in the pillar, coal seam thickness and dip angles, water conditions, water influx rates, mechanical properties of the overburden and strata situated in the seam floor, slope stability and hazards of landslides, effects of water influx on landslide hazards, types of bucket wheel excavators used for overburden removal and mining, types of belt conveyors used for mine haulage, stackers, position of mining equipment in the mine. A scheme developed by Banske Projekty Teplice for partial extraction of the safety pillar would result in extraction of 4.5 Mt coal. About 1.7 Mt coal would be left in a safety coal layer about 10.0 m thick situated in the floor in zones with landslide hazards. KU 300 bucket wheel excavators, belt conveyors 1,200 mm wide and ZP 2,500 stackers would be used. 4 refs.

  17. Strength Reduction of Coal Pillar after CO2 Sequestration in Abandoned Coal Mines

    Directory of Open Access Journals (Sweden)

    Qiuhao Du

    2017-02-01

    Full Text Available CO2 geosequestration is currently considered to be the most effective and economical method to dispose of artificial greenhouse gases. There are a large number of coal mines that will be scrapped, and some of them are located in deep formations in China. CO2 storage in abandoned coal mines will be a potential option for greenhouse gas disposal. However, CO2 trapping in deep coal pillars would induce swelling effects of coal matrix. Adsorption-induced swelling not only modifies the volume and permeability of coal mass, but also causes the basic physical and mechanical properties changing, such as elastic modulus and Poisson ratio. It eventually results in some reduction in pillar strength. Based on the fractional swelling as a function of time and different loading pressure steps, the relationship between volumetric stress and adsorption pressure increment is acquired. Eventually, this paper presents a theory model to analyze the pillar strength reduction after CO2 adsorption. The model provides a method to quantitatively describe the interrelation of volumetric strain, swelling stress, and mechanical strength reduction after gas adsorption under the condition of step-by-step pressure loading and the non-Langmuir isothermal model. The model might have a significantly important implication for predicting the swelling stress and mechanical behaviors of coal pillars during CO2 sequestration in abandoned coal mines.

  18. Time-dependent phosphate dynamics in reclaimed lignite-mine soils under Robinia pseudoacacia L.

    Science.gov (United States)

    Freese, Dirk; Slazak, Anna

    2017-04-01

    As a consequence of the opencast lignite mining activities in Lusatia/Germany, the cultivation of Short Rotation Coppice plantations (SRC) has been considered as a viable option for reclamation purposes. In this region an area of about 1000 km2 has been degraded. Owing to the unfavourable biotic and abiotic properties of the overburden mining substrate, the biogeochemical processes associated with the soil ecosystem development are in the initial phase. The substrate contains very low amount of nutrients, mainly very low total Phosphate (P) content nearly equal to zero. The lack of P is one of the main issues in reclamation of this marginal site. Therefore, the cultivation of perennial SRC with Robinia pseudoacacia L. is considered as a supporting measurement for effective soil reclamation. In this context, it is important to understand the dynamics of P in this "initial substrate" to describe the P availability and P sorption/desorption.. Iron/aluminium oxides and organic matter are the soil constituents most strongly affecting the reactions and rate of P sorption and desorption, also in post-mining soils. Therefore the interaction of these oxides and organic matter with P is essential with regard to developing effective nutrient management strategies for marginal sites. The study focused on P sorption and desorption with regard to different development stages of R. pseudoacacia L. established in a short rotation coppices on the post mining soils. to describe the P availability (Pav) in relation to total P mobility. The hypothesis is that SRC would cause significant changes in soil P dynamics over time in post lignite mining soils. The trees has been planted in between 1995 and 2007, which means that R. pseudoacacia L. was in a range of 2 to 20 years old at different sampling times. Soil was sampled in 2008 and 2015 at three depths of: 0-3cm, 3-10 cm and 10-30 cm. To characterize the P dynamics different P forms and P sorption/desorption kinetics were analysed

  19. Develop guidelines for the design of pillar systems for shallow and intermediate depth, tabular, hard rock mines and provide a methodology for assessing hangingwall stability and support requirements for the panels between pillars

    CSIR Research Space (South Africa)

    York, G

    1998-12-01

    Full Text Available The design of hard rock pillars, in shallow to intermediate depth hard rock mines, has been redefined as the determination of the pillar system load bearing capacity. This entails the ability to design each of the components of the pillar system...

  20. A diverse snake fauna from the early Eocene of Vastan Lignite Mine, Gujarat, India

    Energy Technology Data Exchange (ETDEWEB)

    Rage, J.C.; Folie, A.; Rana, R.S.; Singh, H.; Rose, K.D.; Smith, T. [Museum National Historical Nature, Paris (France)

    2008-09-15

    The early Eocene (Ypresian) Cambay Formation of Vastan Lignite Mine in Gujarat, western India, has produced a diverse assemblage of snakes including at least ten species that belong to the Madtsoiidae, Palaeophiidae (Palaeophis and Pterosphenus), Boidae, and several Caenophidia. Within the latter taxon, the Colubroidea are represented by Russellophis crassus sp. nov. (Russellophiidae) and by Procerophis sahnii gen. et sp. nov. Thaumastophis missiaeni gen. et sp. nov. is a caenophidian of uncertain family assignment. At least two other forms probably represent new genera and species, but they are not named; both appear to be related to the Caenophidia. The number of taxa that represent the Colubroidea or at least the Caenophidia, i.e., advanced snakes, is astonishing for the Eocene. This is consistent with the view that Asia played an important part in the early history of these taxa. The fossils come from marine and continental levels; however, no significant difference is evident between faunas from these levels. The fauna from Vastan Mine includes highly aquatic, amphibious, and terrestrial snakes. All are found in the continental levels, including the aquatic palaeophiids, whereas the marine beds yielded only two taxa. Vastan Mine is only the second locality in which the palaeophiids Palaeophis and Pterosphenus co-occur. The composition of the fauna from Vastan is on the whole similar to that of the early Eocene of Europe; however, comparisons with early Eocene faunas of other continents are not possible because they are poorly known or unknown.

  1. Prevention of ground-water quality degradation during reclamation of a uraniferous lignite mine, North Dakota

    International Nuclear Information System (INIS)

    Houghton, R.L.; Anderson, G.S.; Hill, S.R.; Burgess, J.L.; Wald, J.D.; Patrick, D.P.; Hall, R.L.; Unseth, J.D.

    1987-01-01

    About 590,000 pounds of uranium oxide were recovered from 85,000 tons of lignite in at least 16 North Dakota pits between 1955 and 1967. Because uranium salts in the overburden generally were not recovered, spoil piles at abandoned mine sites contain elevated uranium contents. Reclamation of these mines is required to eliminate public hazards due to elevated radiation and toxic-element levels. A pilot reclamation project was implemented at one abandoned mine pit in northwestern Stark County. Basically, the reclamation involved the replacement of spoil material into the pits from which it was removed. Based on analyses of drill-hole cutting samples obtained from 2-foot depth increments on a 50-foot grid over the 7.25-acre spoil pile, spoil material with radium-226 concentrations exceeding 5 picocuries per gram above background or with uranium concentrations exceeding 5 times background was identified and mapped in three dimensions. This ''most-contaminated'' spoil material was selectively replaced in the mine pits above the water table to prevent dissolution of uranium salts and under a minimum of 5 feed of cover to minimize postreclamation surface-radiation levels. Similarly, areas of spoils with specific conductance greater than 5,000 microsiemens per centimeter were replaced at least 6 feet below the postreclamation ground surface to promote revegetation and above the water table to prevent enrichment of dissolved-solids concentrations in the aquifer. Finally, replaced zones of high radioactivity and soluble salts were capped with clay from the base of an adjacent pit; and the surface topography was mounded to minimize infiltration that might introduce radioactive and other soluble salts into the aquifer

  2. Factors of Reclamation Success at the Lignite Strip-Mined Land in Northern Greece

    Directory of Open Access Journals (Sweden)

    Thomas Panagopoulos

    2013-06-01

    Full Text Available The adverse ecological conditions at the lignite mines of Ptolemaida make the landscape reclamation difficult. The naturally established vegetation and soil properties were studied prior to reclamation. Various forest species were planted to assess the afforestation potential. The natural vegetation was heterogeneous but can be used for the analysis of the site. The soil of the spoil heaps was heterogeneous with unfavourable physicochemical properties. Surface soil temperature was still 24º C higher in bare soil than in soil covered with vegetation. The most successful species of the afforestation trial were Robinia pseudoacacia and Cedrus atlantica. Covering of fly ash spoils with topsoil presented poor results, while sewage sludge gave a favorable amelioration response in areas with high fly ash content. Topsoil from older stands was the suggested method to establish Robinia pseudoacacia. Reclamation success was dependent on appropriate planning; thus, the new landscape had to be designed in harmony with the surrounding landscape before the start of the mining activity.

  3. Colonization of spoil benches of an opencast lignite mine in northwest Spain by amphibians and reptiles

    Energy Technology Data Exchange (ETDEWEB)

    Galan, P. [University of Santiago de Compostela, Santiago de Compostela (Spain). Faculty of Biology

    1997-02-01

    This paper discusses the colonization by reptiles and amphibians of the spoil benches of the Meirama opencast lignite mine in northwest Spain over 10 years, following the start of the revegetation process. At Meirama, spoil benches are initially fertilized and hydroseeded with a pasture mix, but are subject to little subsequent management and are gradually colonized by scrub vegetation characteristic of the region. Herpetofauna censuses were carried out yearly on a single 2 ha plot over 6 years following hydroseeding, and in a single year on ten 2 ha plots which had been hydroseeded between 0 and 10 years previously. In addition, censuses were carried out on three undisturbed `control` plots close to the mine. Fifteen species (nine amphibians and six reptiles) were detected in one or more of the spoil-bench plots. Recolonization was particularly rapid after the first 2-3 years post-hydroseeding, and was closely related to habitat development due to revegetation and natural succession. Species composition was most similar to that in control plots in the oldest (ten-year-old) spoil plots.

  4. Width design for gobs and isolated coal pillars based on overall burst-instability prevention in coal mines

    Directory of Open Access Journals (Sweden)

    Junfei Zhang

    2016-08-01

    Full Text Available An investigation was conducted on the overall burst-instability of isolated coal pillars by means of the possibility index diagnosis method (PIDM. First, the abutment pressure calculation model of the gob in side direction was established to derive the abutment pressure distribution curve of the isolated coal pillar. Second, the overall burst-instability ratio of the isolated coal pillars was defined. Finally, the PIDM was utilized to judge the possibility of overall burst-instability and recoverability of isolated coal pillars. The results show that an overall burst-instability may occur due to a large gob width or a small pillar width. If the width of the isolated coal pillar is not large enough, the shallow coal seam will be damaged at first, and then the high abutment pressure will be transferred to the deep coal seam, which may cause an overall burst-instability accident. This approach can be adopted to design widths of gobs and isolated coal pillars and to evaluate whether an existing isolated coal pillar is recoverable in skip-mining mines.

  5. The application of Airborne Laser Scaning for identifying old lignite workings - case study: the mine "Borussia" near Ośno Lubuskie (Western Poland)

    Science.gov (United States)

    Gontaszewska-Piekarz, Agnieszka; Mrówczyńska, Maria

    2018-04-01

    The paper presents the possibilities of using data obtained by airborne laser scanning for identifying areas where lignite used to be mined. The technology of airborne laser scanning presented in the paper as and its results have a vast potential in terms of identifying local terrain deformations. The paper also presents the history of lignite mining in the region of Ośno Lubuskie (the north-west of Ziemia Lubuska - western Poland). It describes underground mining in complicated geological conditions (glaciotectonic deformations). The paper is supplemented with historical maps showing the locations of the mines

  6. Remote sensing for investigations of woodlands impacted by lignite open surface mines

    Energy Technology Data Exchange (ETDEWEB)

    Pilarski, M. [ILV-Fernerkundung GmbH, Teltow (Germany); Lohstraeter, O. [Abteilung Markscheidewesen, MIBRAG mbH, Theissen (Germany)

    2005-02-01

    The development of a long term monitoring concept for post-mining landscapes and mine surroundings as ordered by the company MIBRAG requires different preliminary studies. Objectives of these methodologically oriented analyses presented were the recording of ecologically relevant parameters, their changes and of possible effects caused by the mining activities in the flood plains of 'Weisse Elster' and 'Schnauder' situated between the open surface lignite mines 'Vereinigtes Schleenhain' and 'Profen' south of Leipzig. Besides other information, repeatedly generated satellite data of the SPOT system was prepared for research of various vegetation types, selected by certain criteria for a long term monitoring. The satellite data analysis methodology and research findings are presented. The generation of radiometrical and comparable data records using the atmosphere correction software 'ATCOR' as part of the image processing system 'ERDAS IMAGINE' and the evaluation of the Normalised Difference Vegetation Index NDVI are important parts of the analysis. Based on deciduous woodland maps near the rivers of 'Weisse Elster' and 'Schnauder', which were categorised as ecologically valuable, statistical analyses were made using the vegetation status evaluated by remote sensing. As a result, tendencies of vegetation change are demonstrated. To obtain more details about special relations between vegetation development and remote sensing data, further research is necessary involving spectral features of deciduous plant canopy and their causalities. Future gathering of high-precision geometric and radiometric (digital airborne) data is one way of reaching more detailed information of the objects in question. The high geometric accuracy of digital camera data (by DMC) and the color bands are benefits for the mining company which can now replace regular air-borne surveying made with analogous technology

  7. Drone-Borne Hyperspectral Monitoring of Acid Mine Drainage: An Example from the Sokolov Lignite District

    Directory of Open Access Journals (Sweden)

    Robert Jackisch

    2018-03-01

    Full Text Available This contribution explores the potential of unmanned aerial systems (UAS to monitor areas affected by acid mine drainage (AMD. AMD is an environmental phenomenon that usually develops in the vicinity of mining operations or in post-mining landscapes. The investigated area covers a re-cultivated tailing in the Sokolov lignite district of the Czech Republic. A high abundance of AMD minerals occurs in a confined space of the selected test site and illustrates potential environmental issues. The mine waste material contains pyrite and its consecutive weathering products, mainly iron hydroxides and oxides. These affect the natural pH values of the Earth’s surface. Prior research done in this area relies on satellite and airborne data, and our approach focuses on lightweight drone systems that enables rapid deployment for field campaigns and consequently-repeated surveys. High spatial image resolutions and precise target determination are additional advantages. Four field and flight campaigns were conducted from April to September 2016. For validation, the waste heap was probed in situ for pH, X-ray fluorescence (XRF, and reflectance spectrometry. Ground truth was achieved by collecting samples that were characterized for pH, X-ray diffraction, and XRF in laboratory conditions. Hyperspectral data were processed and corrected for atmospheric, topographic, and illumination effects using accurate digital elevation models (DEMs. High-resolution point clouds and DEMs were built from drone-borne RGB data using structure-from-motion multi-view-stereo photogrammetry. The supervised classification of hyperspectral image (HSI data suggests the presence of jarosite and goethite minerals associated with the acidic environmental conditions (pH range 2.3–2.8 in situ. We identified specific iron absorption bands in the UAS-HSI data. These features were confirmed by ground-truth spectroscopy. The distribution of in situ pH data validates the UAS-based mineral

  8. Technical and Sociological Investigation of Impacts in Using Lignite Mine Drainage for Irrigation - A Case Study

    Science.gov (United States)

    Murugappan, A.; Manoharan, A.; Senthilkumar, G.; Krishnamurthy, J.

    2017-07-01

    Irrigated farming depends on an ample supply of water compatible quality. Presently, a lot of irrigation projects have to depend on inferior quality and not so enviable sources of water supply. In order to prevent troubles during usage of such water supplies of poor quality, there must be meticulous preparation to ensure that the water available with such quality characteristics is put to best use. The effect of water quality upon soil and crops must be better understood in choosing fitting options to manage with impending water quality associated troubles that might decrease soil and crop productivity under existing circumstances of water use. Two tanks (small sized reservoirs) namely, Walajah Tank and Perumal Tank in Cuddalore District, used for irrigation, receive mine drainage water pumped out continuously from the open cast lignite mines of the NLC India Limited, Neyveli, Tamilnadu State. This water has been used by the farmers in the irrigated commands of both Walajah Tank and Perumal Tank for more than three decades. Recently, the beneficiaries had raised fears on the quality of mine drainage waters they had been using for raising crops in the commands of both the tanks. They opined that the coal dust laden mine water used for irrigation had affected the crop yields. This incited us to take up a study to (i) assess the status of quality of surface waters released from the two tanks for irrigation in the respective command areas and (ii) assess the likely impacts of quality of water on soil and on growth and productivity of crops cultivated in the command areas. Further to the technical evaluation of the impacts, a structured questionnaire survey was also conducted among the farmers and the common public in the study area. The findings of the survey confirmed with the outcome of the technical assessment in that the mine drainage had a poor impact in the cultivable command area of Walajah tank system while such impacts were less significant in most parts of

  9. Restoration of open pit lignite mining in the former GDR: lessons to be learnt from Zwenkau

    Energy Technology Data Exchange (ETDEWEB)

    Wiegand, U.; Schreck, P.; Schreiter, P.; Lerche, I.; Glaesser, W. [Centre for Environmental Research Leipzig-Halle (UFZ), Halle (Germany) Dept. of Hydrogeology

    2003-07-01

    The interactions have been investigated between the near-surface sediments of the sediment dumping at the Zwenkau open pit near Leipzig, used for extraction of lignite, and the produced mining water. These environmental impacts are the legacy of the energy policy of the former GDR. The pyrite oxidation that takes place in the overburden sediments causes the formation of an oxidation front and the pH-value of sediments falls to about 2 to 3 very soon after deposition. The primary mineral contents are destroyed and a considerable number of elements are mobilized that remain locally in the sediment pores. Because of the very weak seepage, rainfall remains in the alluvial areas as so called dump lakes. The dump lakes are very acidic because the rainwater transport the mobilized elements from the surface. Autochthonous and allochthonous formations of secondary minerals have been observed and analysed. A continuously ongoing interaction of exogenous and endogenous effects hinders the hydrological and geochemical equilibrium stabilization. What to do with such a 'moonscape' is considered in the conclusions. 21 refs., 8 figs.

  10. MINE-NEC - A Game for the Analysis of Regional Water Policies in Open-Pit Lignite Mining Areas: An Improved Implementation for the NEC PC-8201A

    OpenAIRE

    Kaden, S.; Varis, O.

    1986-01-01

    The game MINE was developed for the analysis of regional water policies in open-pit lignite mining areas. It is implemented for a GDR test area. The purpose of the game is above all to teach decision makers and their staff in mining regions in order to get a better understanding of the complex interrelated socio-economic processes with respect t o water management in such regions. The game is designed to be played by five groups of players representing municipal and industrial water supply, a...

  11. Palynostratigraphy, palynofacies and depositional environment of a lignite-bearing succession at Surkha Mine, Cambay Basin, north-western India

    Directory of Open Access Journals (Sweden)

    Monga Priyanka

    2015-12-01

    Full Text Available The paper reports palynology and palynofacies studies of lignite-bearing sediments exposed in an opencast mine succession at Surkha, Bhavnagar District, in the coastal region of Gujarat, India. The study examined the relationships between the palynoflora, sedimentary organic matter and environment at the time of deposition of lignite and associated sediments. Based on dinoflagellate cyst biostratigraphy, the sedimentary succession is dated as early Eocene (Ypresian. Palynofacies studies helped reveal the palaeoenvironmental fluctuations. The dominance of angiosperm pollen grains, freshwater algae, microthyraceous fungi and a large share of land debris in the lower part of the succession suggests a freshwater swamp environment of deposition for the basal lignite facies. Two cenozones - Matanomadiasulcites maximus and Lakiapollis ovatus - were identified in the lower lignite facies, determined from the dominance of these pollen grains in the palynological assemblages. The presence of angiosperm pollen grains and pteridophyte spores in the carbonaceous shale horizon above the lignite facies indicates a change in the depositional regime from freshwater swamp to lagoonal. This was identified as the Arecipites wodehousei cenozone due to its numerical abundance in the assemblage. Dinoflagellate cyst abundance and diversity, and microforaminiferal test linings along with well-sorted terrestrial debris in the mudstone in the upper part of the succession suggest a more open marine estuarine type of depositional environment. The Homotryblium complex along with Cordospheridium fibrospinosum, Kenleyia sp., and Thalassiphora pelagica dinoflagellate cysts are the main representatives of this zone, determined as the Homotryblium tenuispinosum cenozone. The changing depositional settings (freshwater swamp-lagoonal-estuarine along the vertical succession indicate a marine transgression in this region. Results from palynological studies of early Palaeogene

  12. Evaluation of naturally occurring pigments of the North Bohemian lignite mining area; Bewertung von mineralischen Pigmentvorkommen des nordboehmischen Braunkohlenbeckens

    Energy Technology Data Exchange (ETDEWEB)

    Buntenbach, Stephan [TriMin Consulting - Mineral Processing, Ammerthal (Germany); Botula, Jiri [VSB-Technical Univ. of Ostrava (Czech Republic). Mineral Processing Dept.; Leonhardt, Hana

    2010-11-15

    The research project ''Mineral Processing Methods for the Preparation of Naturally Occurring Pigments from Overburden of the Lignite Mines and from Shallow Clay Deposits of the North Bohemian Lignite Basin'', funded by the Deutsche Bundesstiftung Umwelt DBU, was conducted as a collaboration between the AKW Apparate+Verfahren GmbH, Hirschau with the Technical University of Ostrava. Geological, mineralogical and mineral processing studies for the development of a suitable beneficiation method were carried out to investigate the possibilities of the industrial usage of beneficiated pigments of these deposits. It should be demonstrated, that the significant reserves of mineral pigments in the shallow deposits and also in the overburden of the lignite mines can be utilized ecologically and economically. Based on the results of geological prospecting work already carried out, the deposit Horenec was selected as the most important pigment deposits for the production of bolus and ochre earth. The newly carried out geological, mineralogical and chemical studies formed the basis for the following mineral processing test work and the test work for the usage of beneficiated products as colouring paint for plastic, fabric and other materials. (orig.)

  13. Chemical characterization and receptor modeling of PM10 in the surroundings of the opencast lignite mines of Western Macedonia, Greece.

    Science.gov (United States)

    Samara, Constantini; Argyropoulos, George; Grigoratos, Theodoros; Kouras, Αthanasios; Manoli, Εvangelia; Andreadou, Symela; Pavloudakis, Fragkiskos; Sahanidis, Chariton

    2018-05-01

    The Western Macedonian Lignite Center (WMLC) in northwestern Greece is the major lignite center in the Balkans feeding four major power plants of total power exceeding 4 GW. Concentrations of PM 10 (i.e., particulate matters with diameters ≤10 μm) are the main concern in the region, and the high levels observed are often attributed to the activities related to power generation. In this study, the contribution of fugitive dust emissions from the opencast lignite mines to the ambient levels of PM 10 in the surroundings was estimated by performing chemical mass balance (CMB) receptor modeling. For this purpose, PM 10 samples were concurrently collected at four receptor sites located in the periphery of the mine area during the cold and the warm periods of the year (November-December 2011 and August-September 2012), and analyzed for a total of 26 macro- and trace elements and ionic species (sulfate, nitrate, chloride). The robotic chemical mass balance (RCMB) model was employed for source identification/apportionment of PM 10 at each receptor site using as inputs the ambient concentrations and the chemical profiles of various sources including the major mine operations, the fly ash escaping the electrostatic filters of the power plants, and other primary and secondary sources. Mean measured PM 10 concentrations at the different sites ranged from 38 to 72 μg m -3 . The estimated total contribution of mines ranged between 9 and 22% in the cold period increasing to 36-42% in the dry warm period. Other significant sources were vehicular traffic, biomass burning, and secondary sulfate and nitrate aerosol. These results imply that more efficient measures to prevent and suppress fugitive dust emissions from the mines are needed.

  14. Aquatic balance in Vegoritis Lake, West Macedonia, Greece, relating to lignite mining works in the area

    Science.gov (United States)

    Dimitrakopoulos, D.; Grigorakou, E.; Koumantakis, J.

    2003-04-01

    . The dewatering of the aquifers for the protection of the lignite mine seems to have an insignificant influence on the aquatic balance, as the water is discharged again into the streams and rivers of the closed basin.

  15. Development of a time-dependent energy model to calculate the mining-induced stress over gates and pillars

    Directory of Open Access Journals (Sweden)

    Mohammad Rezaei

    2015-06-01

    Full Text Available Generally, longwall mining-induced stress results from the stress relaxation due to destressed zone that occurs above the mined panel. Knowledge of induced stress is very important for accurate design of adjacent gateroads and intervening pillars which helps to raise the safety and productivity of longwall mining operations. This study presents a novel time-dependent analytical model for determination of the longwall mining-induced stress and investigates the coefficient of stress concentration over adjacent gates and pillars. The model is developed based on the strain energy balance in longwall mining incorporated to a rheological constitutive model of caved materials with time-varying parameters. The study site is the Tabas coal mine of Iran. In the proposed model, height of destressed zone above the mined panel, total longwall mining-induced stress, abutment angle, induced vertical stress, and coefficient of stress concentration over neighboring gates and intervening pillars are calculated. To evaluate the effect of proposed model parameters on the coefficient of stress concentration due to longwall mining, sensitivity analysis is performed based on the field data and experimental constants. Also, the results of the proposed model are compared with those of existing models. The comparative results confirm a good agreement between the proposed model and the in situ measurements. According to the obtained results, it is concluded that the proposed model can be successfully used to calculate the longwall mining-induced stress. Therefore, the optimum design of gate supports and pillar dimensions would be attainable which helps to increase the mining efficiency.

  16. The lignite industry and regional development. Interactions exemplified by the Rhenish mining area

    International Nuclear Information System (INIS)

    Kulik, Lars; Voigt, Jens

    2013-01-01

    Even in times of globalised markets, the German lignite industry retains its local and regional roots. Viewed against this background, the relationship between lignite industry and regional actors, and the interactions between the two play a major role in the perspectives for this branch of Germany's energy sector. Today, the links between the lignite industry and regional bodies are those of a partnership at eye-level. This type of relationship between the industry and regional actors has led to new forms and methods of cooperation at various levels. This is particularly evident in the efforts to re-shape the regional structure, develop the structure of townships and strengthen the economic structure with lignite playing an important role and new partners which are gaining in importance. (orig.)

  17. Mining the 510 coal seam prone to rock bursts and below a coal support pillar in a seam above

    Energy Technology Data Exchange (ETDEWEB)

    Major, M; Gebala, W

    1983-10-01

    The 510 coal seam, situated at a depth of 760 m below a support pillar left in an overlying coal seam, was mined by a system of longwall faces from 1979 to 1982. The seam was prone to rock bursts. Energy of rock bursts which occurred in the mine ranged from 10/SUP/5 to 10/SUP/6 J. The coal seam, 10 m thick, was mined by slicing. Faces were 140 m long. Stress concentrations caused by the suppport pillar left in the overlying coal seam were calculated. Curves which describe stress fluctuations were plotted. Rock burst hazards were determined by drilling. Drilling intervals depended on hazard degree and position of the test site in relation to the support pillar in the overlying coal seam. The face was 3 m high. Supports used in 2 gate roads were reinforced by steel and timber supports. Strong timber boards were placed at canopies of powered supports used at the working face. The face was situated at an angle of 10 degrees to the pillar axis. In the zone of critical stresses water infusion and shock blasting were used for rock burst prevention. These methods, plus reinforcement of the supports in gate roads and at the working face, guaranteed safe mining and prevented rock bursts. (8 refs.)

  18. Scientific investigations accompanying recultivation of abandoned lignite mines in East Germany. Research projects 1994 through 2000; Wissenschaftliche Begleitung der ostdeutschen Braunkohlesanierung. Forschungsprojekte 1994 bis 2000

    Energy Technology Data Exchange (ETDEWEB)

    Gockel, G.; Hildmann, E.; Schlenstedt, J.; Schreiber, M. (comps.)

    2001-07-01

    From 1990 the reduction of lignite mining on the territory of the German Democratic Republic (GDR) led to the closure of plants for the production and processing of lignite. This entailed a dramatic demand of redevelopment and transformation of former mining and industrial areas of lignite industry and the creation of the industrial branch of remediation of post-lignite-mining areas, for which suitable structures of management and financing had to be found. The target of these endeavours is the creation of multifunctional to follow former surface mining areas. Ecological and security criteria play an eminent part in this process. Stabilising slopes, recultivation, rehabilitation of a balanced water regime and the elimination of dangers emanating from groundwater and soil contamination by earlier industrial use have particular priority. Recultivation requires scientific preparation and surveillance. Deficits are discussed that have led to the invitation of tenders for a promotion initiative and resulted in the implementation of a number of research projects. This publication deals with the presentation of the tasks and research approaches as well as the description and evaluation of results with the view of their applicability. (orig.)

  19. Weathering processes under various moisture conditions in a lignite mine spoil from As Pontes (N.W. Spain)

    International Nuclear Information System (INIS)

    Seoane, S.; Leiros, M.C.

    1997-01-01

    Processes contributing to acid release/consumption during weathering of a lignite mine spoil (2.3% w/w S as sulfides) from As Pontes (N.W. Spain) were studied under three moisture conditions (at field capacity or under alternate wetting-drying or forced percolation), which were simulated in laboratory experiments. Oxidation of sulfides to sulfates was favoured under all three moisture conditions, releasing most acid in spoil kept at field capacity. Hydroxysulfates formed in spoil kept at field capacity or under alternate wetting-drying conditions, thereby contributing to acid release. Acid consumption by dissolution of clay minerals, especially micas, was favoured under all three moisture conditions, but was particularly intense in spoil at field capacity. Dissolution of aluminium oxides was also favoured under all the moisture conditions studied. 27 refs., 8 figs., 6 tabs

  20. Verification of the fulfilment of the purposes of Basel II, Pillar 3 through application of the web log mining methods

    Directory of Open Access Journals (Sweden)

    M. Munk

    2012-01-01

    Full Text Available The objective of the paper is the verification of the fulfilment of the purposes of Basel II, Pillar 3 – market discipline during the recent financial crisis. The objective of the paper is to describe the current state of the working out of the project that is focused on the analysis of the market participants’ interest in mandatory disclosure of financial information by a commercial bank by means of advanced methods of web log mining. The output of the realized project will be the verification of the assumptions related to the purposes of Basel III by means of the web mining methods, the recommendations for possible reduction of mandatory disclosure of information under Basel II and III, the proposal of the methodology for data preparation for web log mining in this application domain and the generalised procedure for users’ behaviour modelling dependent on time. The schedule of the project has been divided into three phases. The paper deals with its first phase that is focusing on the data pre-processing, analysis and evaluation of the required information under Basel II, Pillar 3 since 2008 and its disclosure into the web site of a commercial bank. The authors introduce the methodologies for data preparation and known heuristic methods for path completion into web log files with respect to the particularity of investigated application domain. They propose scientific methods for modelling users’ behaviour of the webpages related to Pillar 3 with respect to time.

  1. Restoration of the water balance in the lignite mining areas of central Germany and Lusatia; Sanierung des Wasserhaushalts in den Braunkohlenbergbaugebieten Mitteldeutschlands und der Lausitz

    Energy Technology Data Exchange (ETDEWEB)

    Benthaus, Friedrich-Carl [Lausitzer und Mitteldeutsche Bergbau-Verwaltungsgesellschaft mbH (LMBV), Senftenberg (Germany). Ingenieurbereich Sanierung, Strategie und Entwicklung; Scholz, Eckhard [Lausitzer und Mitteldeutsche Bergbau-Verwaltungsgesellschaft mbH (LMBV), Senftenberg (Germany). Ingenieurbereich Sanierung; Uhlig, Christiane [Lausitzer und Mitteldeutsche Bergbau-Verwaltungsgesellschaft mbH (LMBV), Senftenberg (Germany). Ingenieurbereich Sanierung, Geotechnik Mitteldeutschland; Heine, Rudi [Lausitzer und Mitteldeutsche Bergbau-Verwaltungsgesellschaft mbH (LMBV), Senftenberg (Germany). Ingenieurbereich Sanierung, Planung Wasserbau Lausitz; Totsche, Oliver [Lausitzer und Mitteldeutsche Bergbau-Verwaltungsgesellschaft mbH (LMBV), Senftenberg (Germany). Ingenieurbereich Sanierung, Geotechnik Lausitz

    2010-10-15

    The lignite mining industry in central Germany and Lusatia has interfered with the water balance in the regions by long-standing lowering of the ground water and changing of the surface waters. The restoration is aimed at re-establishment of a largely self-regulating water balance by flooding and aftercare. The planning of the linkage of the 220 lakes in the aftermath of the mining industry to the public waterway network should be based on the conditions prevailing after abandonment of the mining industry. Innovative geochemical and biological processes are being further developed to improve the water quality, which is characterised by oxidation of the iron sulphides. (orig.)

  2. Petrography and geochemistry of selected lignite beds in the Gibbons Creek mine (Manning Formation, Jackson Group, Paleocene) of east-central Texas

    Science.gov (United States)

    Warwick, Peter D.; Crowley, Sharon S.; Ruppert, Leslie F.; Pontolillo, James

    1997-01-01

    This study examined the petrographic and geochemical characteristics of two lignite beds (3500 and 4500 beds, Manning Formation, Jackson Group, Eocene) that are mined at the Gibbons Creek mine in east-central Texas. The purpose of the study was to identify the relations among sample ash yield, coal petrography, and trace-element concentrations in lignite and adjoining rock layers of the Gibbons Creek mine. Particular interest was given to the distribution of 12 environmentally sensitive trace elements (As, Be, Cd, Cr, Co, Hg, Mn, Ni, Pb, Sb, Se, and U) that have been identified as potentially hazardous air pollutants (HAPs) in the United States Clean Air Act Amendments of 1990. Eleven lignite, floor, and rock parting samples were collected from incremental channel samples of the 3500 and 4500 beds that were exposed in a highwall of pit A3 at the Gibbons Creek mine. Short proximate and ultimate and forms of sulfur analyses were performed on all lignite samples, and lignite and rock samples were analyzed for 60 major, minor and trace elements. Representative splits of all lignite samples were ground and cast into pellets, and polished for petrographic analyses in blue-light fluorescence and reflected white light to determine liptinite, inertinite, and huminite maceral group percentages. The following observations summarize our results and conclusions about the geochemistry, petrography, and sedimentology of the 3500 and 4500 beds of the Gibbons Creek lignite deposit: (1) Weighted average dry (db) ash yield for the two beds is 29.7%, average total sulfur content is 2.6%, and average calorific value is 7832 Btu (18.22 MJ/kg). Ash yields are greatest in the lower bench (59.33% db) of the 3500 bed and in the upper bench of the 4500 bed (74.61% db). (2) For lignite samples (on a whole-coal basis), the distributions of two of the HAPs (Pb and Sb) are positively related to ash yield, probably indicating an inorganic affinity for these elements. By using cluster analysis we

  3. Tanacetum vulgare as a bioindicator of trace-metal contamination: a study of a naturally colonized open-pit lignite mine.

    Science.gov (United States)

    Jasion, Mateusz; Samecka-Cymerman, Aleksandra; Kolon, Krzysztof; Kempers, Alexander J

    2013-10-01

    We investigated the possibility of use of Tanacetum vulgare (tansy) as an ecological indicator of metal concentration in a naturally colonized open-pit lignite mine in Bełchatów (Poland). Tanacetum vulgare is the only species growing abundantly and spontaneously in the lignite mine waste dumps. Metal concentrations in roots, stems, leaves, flowers, and soil were measured in dump sites differing in type and time of reclamation and therefore differing in pollution levels. Tanacetum vulgare appeared to be an accumulator of chromium and iron in roots, whereas highest concentrations of manganese and zinc were found in leaves. A high bioaccumulation factor for cadmium (Cd) was observed in dumps and control sites, indicating that even small amounts of Cd in the environment may result in significant uptake by the plant. The lowest concentrations of metals were found in plants from sites situated on dumps reclaimed with argillaceous limestone.

  4. From old lignite mining pits to new lakes. The example of rehabilitation of the former open-cast mining facilities at Berzdorf, Germany; Von alten Gruben zu neuen Seen am Beispiel des Tagebaues Berzdorf

    Energy Technology Data Exchange (ETDEWEB)

    Kolba, Manfred [LMBV mbH, Sanierungsbereich Lausitz, Senftenberg (Germany)

    2009-09-15

    The Lausitz and Central-German Mining Administration Company (LMBV) is project executor for the largest landscaping construction site in Europe. LMBV rehabilitates former open-cast mining facilities, as well as decommissioned coal-upgrading plants, to provide promising future areas for industrial complexes, and for landscapes that will attract a great number and variety of tourism developments. LMBV executes projects for the elimination of dangers as a result of the rising of groundwater to its former and natural level. In this context, the German Federal States involved in past and present lignite mining support extensive measures for enhancement of the standard of future use at the new lakes in Central Germany and in the Lausitz Region. This presentation shows the rehabilitation activities of LMBV as project executor in a great range of activities, by explaining the rehabilitation and transformation of the former lignite mining facilities in Berzdorf, Germany, in creation of the future Berzdorf Lake. (orig.)

  5. Potential climate change impacts on water availability and cooling water demand in the Lusatian Lignite Mining Region, Central Europe

    Science.gov (United States)

    Pohle, Ina; Koch, Hagen; Gädeke, Anne; Grünewald, Uwe; Kaltofen, Michael; Redetzky, Michael

    2014-05-01

    In the catchments of the rivers Schwarze Elster, Spree and Lusatian Neisse, hydrologic and socioeconomic systems are coupled via a complex water management system in which water users, reservoirs and water transfers are included. Lignite mining and electricity production are major water users in the region: To allow for open pit lignite mining, ground water is depleted and released into the river system while cooling water is used in the thermal power plants. In order to assess potential climate change impacts on water availability in the catchments as well as on the water demand of the thermal power plants, a climate change impact assessment was performed using the hydrological model SWIM and the long term water management model WBalMo. The potential impacts of climate change were considered by using three regional climate change scenarios of the statistical regional climate model STAR assuming a further temperature increase of 0, 2 or 3 K by the year 2050 in the region respectively. Furthermore, scenarios assuming decreasing mining activities in terms of a decreasing groundwater depression cone, lower mining water discharges, and reduced cooling water demand of the thermal power plants are considered. In the standard version of the WBalMo model cooling water demand is considered as static with regard to climate variables. However, changes in the future cooling water demand over time according to the plans of the local mining and power plant operator are considered. In order to account for climate change impacts on the cooling water demand of the thermal power plants, a dynamical approach for calculating water demand was implemented in WBalMo. As this approach is based on air temperature and air humidity, the projected air temperature and air humidity of the climate scenarios at the locations of the power plants are included in the calculation. Due to increasing temperature and decreasing precipitation declining natural and managed discharges, and hence a lower

  6. Lignite boost for North. [Northern Ireland

    Energy Technology Data Exchange (ETDEWEB)

    Clerkin, H.

    1986-01-01

    Reserves of lignite, estimated at around 500 million tonnes, have been discovered on the shores of Lough Neagh, Northern Ireland. The Government has granted a mining licence and planning permission to Burnett and Hallamshire Holdings to start work on the deposit. It is proposed to mine the lignite using opencast methods. Much of this deposit will be consumed in a purpose-built mine mouth power station with further reserves being dried in the approved processing plant to produce a range of industrial and domestic fuels. Carbonising the lignite may eliminate pollution. However, large scale investment will be required before Ireland's economy can switch to lignite.

  7. Landscaping and ecology in the lignite mining area of Maritza-East, Bulgaria

    International Nuclear Information System (INIS)

    Haege, K.; Drebenstedt, C.; Angelov, E.

    1996-01-01

    The study on the future mining concept of the open-cast mine Trojovano-North, Bulgaria which is presented in this paper was prepared in close cooperation with Bulgarian specialists. It particularly takes into account ecological aspects. The mining concept clearly shows that economy and ecology can be combined usefully. The advantages are, among others, reduced occupation of land, avoiding of river and village translocation and the efficient use of chernozems for topsoil. Various landscape elements are used for the improvement of the ecological conditions in this intensively agricultural area. The illustrated measures show that the mining impacts on nature can be limited, minimized and balanced. It is possible to win the required public acceptance. 3 refs., 3 figs., 2 tabs

  8. Using radon-222 for tracing groundwater discharge into an open-pit lignite mining lake--a case study.

    Science.gov (United States)

    Schmidt, Axel; Schubert, Michael

    2007-12-01

    Groundwater discharge into an open pit lignite mining lake was investigated using radon-222 as a naturally occurring environmental tracer. The chosen study site was a meromictic lake, i.e., a water body that is divided horizontally into two separate layers--the upper mixolimnion (with seasonal mixing) and the lower monimolimnion (without seasonal mixing). For the estimation of groundwater discharge rates into the lake, a simple box model including all radon sinks and sources related to each layer was applied. Two field investigations were performed. During the October campaign, the total groundwater discharge into the lake was found to be 18.9 and 0.7 m(3) d(-1) for the mixolimnion and monimolimnion, respectively. During the December campaign, the groundwater discharge into the mixolimnion was 15.0 m(3) d(-1), whereas no discharge at all was observed into the monimolimnion. Based on the given water volumes, the residence time of lake water was 5.3 years for the monimolimnion and varies between 0.9 and 1.1 years for the mixolimnion. The investigation confirmed radon to be a useful environmental tracer for groundwater and surface water interactions in meromictic lake environments.

  9. Soil restoration under pasture after lignite mining - management effects on soil biochemical properties and their relationships with herbage yields

    Energy Technology Data Exchange (ETDEWEB)

    Ross, D.J.; Speir, T.W.; Cowling, J.C.; Feltham, C.W. (DSIR, Lower Hutt (New Zealand))

    1992-01-01

    The recovery of soil biochemical properties under grazed, grass-clover pasture after simulated lignite mining was studied over a 5-year period in a mesic Typic Dystrochrept soil at Waimumu, Southland, New Zealand. Restoration procedures involved four replacement treatments, after A,B and C horizon materials had been separately removed, from all except the control, and stockpiled for 2-3 weeks. Replacement treatment markedly influenced the recovery of herbage production and soil organic C and total N contents, N mineralization, microbial biomass (as indicated by mineral-N flush) and invertase and sulphatase activities. The effectiveness of replacement treatments decreased in the order: 1. control (no stripping or replacement). 2. A,B and C horizon materials replaced in the same order. 3. A,B and C horizon materials each mixed with an equal amount of siltstone overburden and replaced in order, 4. A and B horizon materials mixed before replacing over C horizon materials. Ripping increased herbage production, net N mineralization and microbial biomass. Fertilizer N also stimulated herbage production but depressed clover growth. Increases in soil invertase and, to a lesser extent, sulphatase activity were closely related to changes in herbage production. Microbial biomass increased more rapidly than soil organic C in early stages in the trial. Rates of net N mineralization suggest that N availability would have limited pasture growth.

  10. Natural radioactivity in lignite samples from open pit mines “Kolubara”, Serbia – risk assessment

    International Nuclear Information System (INIS)

    Đurašević, M.; Kandić, A.; Stefanović, P.; Vukanac, I.; Šešlak, B.; Milošević, Z.; Marković, T.

    2014-01-01

    Coal as fossil fuel mainly contains naturally occurring radionuclides from the uranium and thorium series and 40 K. Use of coal, primarily in industry, as a result has dispersion of radioactive material from coal in and through air and water. The aim of this study was to determine the activity concentrations of natural radionuclides in coal samples from open pit mines “Kolubara” and to evaluate its effect on population health. The results showed that all measured and calculated values were below the limits recommended in international legislation. - Highlights: • Activity concentrations of natural radionuclides in coal samples were determined. • Effect on population health due to the activity of these radionuclides was estimated. • All samples were collected at different locations of the open pit mines “Kolubara”. • All measured and calculated values were below the recommended limits. • There is no enhanced radiation hazard for population nearby open pit mines

  11. Revegetation of lignite mining areas for sustainable agricultural use - research results and current information needs; Rekultivierung von Braunkohlebergbauflaechen fuer eine nachhaltige landwirtschaftliche Nutzung - Bisherige Forschungsergebnisse und aktueller Forschungsbedarf

    Energy Technology Data Exchange (ETDEWEB)

    Haubold-Rosar, M. [Forschungsinstitut fuer Bergbaufolgelandschaften e.V., Finsterwalde (Germany)

    2004-07-01

    The author explains the reasons and motives for agricultural reclamation which is still necessary in the mining districts of 'the New Laender'. Reclamation has to be aimed at the general objectives of a sustainable land use. The procedures of reclamation have to consider the special site conditions on the dumps. First of all they serve for the development of soil fertility. Proceeding from the research on agricultural reclamation carried out before 1990 the need of research at the beginning of the BMBF priority programme 'Rehabilitation and reclamation of landscapes after lignite mining in the New Laender' and the gained knowledge are given dealing with the topics: use and amelioration of cohesive mine soils, cultivation of alternative crops and pasture usage in post mining landscapes as well as application of soil improvers out of organic waste materials. Finally current deficits of knowledge are pointed out. (orig.)

  12. Hydrogeochemical Processes Causing Persistent Low pH in Lakes within a Reclaimed Lignite Mine, East Texas

    Science.gov (United States)

    Paul, J. C.; Schwab, P.; Knappett, P.; Deng, Y.

    2017-12-01

    Surface water pH values ranging from 2.5 to 2.6 have been reported in three lakes at a reclaimed lignite mine located in the Wilcox Formation of East Texas (the site). Traditional neutralization processes using alkaline chemicals to neutralize the surface water were found to be temporary solutions at the site. Low pH conditions usually are caused by oxidation of pyritic materials in the original tailings, but that was not always apparent based on previous studies at this site. The objective of this study is to determine factors contributing to acid seepage to aid in developing pre- and post-mining strategies to mitigate persistent acidity in surface waters at this and other sites. Mineralogy, hydrogeology, and hydrogeochemical reactions were evaluated. A network of 30 wells was used to monitor the water table and chemistry of the shallow, unconfined aquifer surrounding the lakes. Pressure transducers were deployed in 18 of these wells and each of the lakes to measure high frequency water levels over approximately one year. These water levels were contoured to visualize changing hydraulic head over time and determine the correlation in time between ground water flow directions and local rainfall events. Boreholes at 15 of the monitoring wells were continuously cored, and samples were taken at selected depth intervals based on pH measurements. XRD, SEM, and TEM were used to determine the mineralogy of select soil samples. Ion chromatography was used to determine sulfate concentration, and ICP-MS was used to determine solute concentrations from water and digested soil samples. Framboidal and microcrystalline pyrite were identified in the vadose zone in silt and clay-sized fractions; these minerals have high surface area that is conducive to rapid oxidation and acidification as ground water permeates from the vadose into the saturated zone. Morphology in addition to quantity of weatherable pyrite plays a significant role in acidification. Computer models were used to

  13. Purification of mine water: Meirama lignite. Depuracion de las aguas de minas: lignitos de Meirama

    Energy Technology Data Exchange (ETDEWEB)

    Herranz Villafruela, F. (Lignitos de Meirama (Spain))

    1992-04-01

    The Meirama hydrographic basin covers 33 square kilometres and has an average annual precipitation of between 1,100 and 1,900 mm. Since 1975 when measurements began, the annual average has been 1,500 mm. The area enclosed by water channels is 3.4 square kilometres. For the average annual rainfall of 1,500 mm, this gives nearly five million cubic metres of water per year. When this total is added to the 950,000 cubic metres of phreatic water measured to date, it creates the need for a pump capable of moving approximately 650 cubic metres per hour the whole year round, allowing a factor of 0.8 for evaporation and run-off. In order to facilitate drainage over the whole of the working area, the mine has been planned so as to give a rising 1% gradient toward the benches starting from an imaginary line which divides the mine into one third and two thirds of its total length where the settling ponds and pump are situated. Although this system made the mining project more complicated, it was very successful as it made it possible to keep the machinery on well-drained ground. 4 figs., 1 tab.

  14. Determining the area of influence of depression cone in the vicinity of lignite mine by means of triangle method and LANDSAT TM/ETM+ satellite images.

    Science.gov (United States)

    Zawadzki, Jarosław; Przeździecki, Karol; Miatkowski, Zygmunt

    2016-01-15

    Problems with lowering of water table are common all over the world. Intensive pumping of water from aquifers for consumption, irrigation, industrial or mining purposes often causes groundwater depletion and results in the formation of cone of depression. This can severely decrease water pressure, even over vast areas, and can create severe problems such as degradation of agriculture or natural environment sometimes depriving people and animals of water supply. In this paper, the authors present a method for determining the area of influence of a groundwater depression cone resulting from prolonged drainage, by means of satellite images in optical, near infrared and thermal infrared bands from TM sensor (Thematic Mapper) and ETM+ sensor (Enhanced Thematic Mapper +) placed on Landsat 5 and Landsat 7 satellites. The research area was Szczercowska Valley (Pol. Kotlina Szczercowska), Central Poland, located within a range of influence of a groundwater drainage system of the lignite coal mine in Belchatow. It is the biggest lignite coal mine in Poland and one of the largest in Europe exerting an enormous impact on the environment. The main method of satellite data analysis for determining soil moisture, was the so-called triangle method. This method, based on TVDI (Temperature Vegetation Dryness Index) was supported by additional spatial analysis including ordinary kriging used in order to combine fragmentary information obtained from areas covered by meadows. The results obtained are encouraging and confirm the usefulness of the triangle method not only for soil moisture determination but also for assessment of the temporal and spatial changes in the area influenced by the groundwater depression cone. The range of impact of the groundwater depression cone determined by means of above-described remote sensing analysis shows good agreement with that determined by ground measurements. The developed satellite method is much faster and cheaper than in-situ measurements

  15. Phototrophic biofilms of restored fields in the Rhenish lignite mining area: development of soil algal, bacterial, and fungal biomasses

    Energy Technology Data Exchange (ETDEWEB)

    Jahnke, K.; Priefer, U.B. [Rhein Westfal TH Aachen, Aachen (Germany)

    2002-07-01

    The formation of phototrophic biofilms in three fields under restoration of a lignite-mining area was recorded over 3 years of lucerne cultivation in terms of biomass carbon from algae, bacteria and fungi. The primary phase of biofilm development on the humus- and nitrogen deficient uppermost soil surfaces was dominated by algae. The ratio of algal carbon to heterotrophic bacterial and fungal carbon ranged from 1:0.4 to 1:2. Only during this initial developmental stage did the total microfloral carbon exceed 10% of the overall organic carbon content. With time, the ratios between algal and heterotrophic microbial carbon increased to 1:10 which was mainly due to decomposed plant residues and humus accumulation supporting the growth of bacteria and fungi. At this later stage of field development the calculated amount of bacterial and fungal carbon associated with the algae was still at least 8% of total heterotrophic microbial carbon and could even reach 20%. Bacterial and fungal biomasses were primarily governed by the organic carbon content (r = 0.81), but fluctuations-up to 50% and occurring mostly simultaneously for the three microfloral members-were observed in response to temperature and moisture conditions. The calculated in situ doubling times were 8 days (algae), 9 days (bacteria) and 14 days (fungi), respectively. Insight is given into the dynamics of phototrophic biofilm development and the abiotic factors affecting them during early phases of arable soil restoration. The results indicate that biomass changes expressed as the respective ratios between their microfloral members are a useful tool to characterise the different developmental stages of terrestrial biofilms.

  16. Natural radioactivity in lignite samples from open pit mines "Kolubara", Serbia--risk assessment.

    Science.gov (United States)

    Ðurašević, M; Kandić, A; Stefanović, P; Vukanac, I; Sešlak, B; Milošević, Z; Marković, T

    2014-05-01

    Coal as fossil fuel mainly contains naturally occurring radionuclides from the uranium and thorium series and (40)K. Use of coal, primarily in industry, as a result has dispersion of radioactive material from coal in and through air and water. The aim of this study was to determine the activity concentrations of natural radionuclides in coal samples from open pit mines "Kolubara" and to evaluate its effect on population health. The results showed that all measured and calculated values were below the limits recommended in international legislation. © 2013 Published by Elsevier Ltd.

  17. Lignite microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Bulankina, M.A.; Lysak, L.V.; Zvyagintsev, D.G. [Moscow MV Lomonosov State University, Moscow (Russian Federation). Faculty of Soil Science

    2007-03-15

    The first demonstration that samples of lignite at a depth of 10 m are considerably enriched in bacteria is reported. According to direct microscopy, the abundance of bacteria was about 10{sup 7} cells/g. About 70% of cells had intact cell membranes and small size, which points to their anabiotic state. The fungal mycelium length was no more than 1 m. Lignite inoculation onto solid glucose-yeast-peptone medium allowed us to isolate bacteria of the genera Bacillus, Rhodococcus, Arthrobacter, Micrococcus, Spirillum, and Cytophaga. Representatives of the genera Penicillium and Trichoderma were identified on Czapek medium. Moistening of lignite powder increased the microbial respiration rate and microbial and fungal abundance but did not increase their generic diversity. This finding suggests that the studied microorganisms are autochthonous to lignite.

  18. Forecast and Prevention of Coal and Gas Outbursts in the Case of Application of a New Mining Method - Drilling of a Coal Pillar

    Directory of Open Access Journals (Sweden)

    Vlastimil Hudeček

    2010-10-01

    Full Text Available Coal and gas outbursts are one of risk factors accompanying the mining of coal in low seams in the Ostrava-Karviná Coalfield.At the use of the method of longwall mining, all coal reserves have not been mined out owing to tectonic faults. For mining outthe residual reserves, the application of a new mining method - drilling of a coal pillar was proposed.The method of mining of a coal seam utilizing long large diameter boreholes is verified in the Paskov Mine (company OKD, JSC –Czech Republic under conditions of rock mass with hazard of rock and gas outbursts in localities of residual pillars left in seams afterfinishing the mining operations performed with using the classical method of longwall working along the strike. [5]Forecast and preventive measures applied to the verification of the new method were based on previous experience withthe mining of seams with hazard of coal and gas outbursts. They accepted fully valid legislation, i.e. Ordinance of Ostrava RegionalMining Authority No. 3895/2002 and supplementary materials (Instructions and Guidelines. The proposed measures respectedthe character of the method being verified. [4]For all areas being mined, projects containing also chapters specifying the problems of ensuring the safety of mining worksand operation under conditions of hazard of coal and gas outbursts were prepared.In the contributions, basic proposals for the principles of coal and gas outburst forecast and prevention when applying the newmining method – drilling of a coal pillar are presented

  19. Biomass production as renewable energy resource at reclaimed Serbian lignite open-cast mines

    Directory of Open Access Journals (Sweden)

    Jakovljević Milan

    2015-01-01

    Full Text Available The main goal of this paper is the overview of the scope and dynamics of biomass production as a renewable energy source for substitution of coal in the production of electrical energy in the Kolubara coal basin. In order to successfully realize this goal, it was necessary to develop a dynamic model of the process of coal production, overburden dumping and re-cultivation of dumping sites by biomass planting. The results obtained by simulation of the dynamic model of biomass production in Kolubara mine basin until year 2045 show that 6870 hectares of overburden waste dumps will be re-cultivated by biomass plantations. Biomass production modeling point out the significant benefits of biomass production by planting the willow Salix viminalis cultivated for energy purposes. Under these conditions, a 0.6 % participation of biomass at the end of the period of intensive coal production, year 2037, is achieved. With the decrease of coal production to 15 million tons per year, this percentage steeply rises to 1.4 % in 2045. This amount of equivalent tons of coal from biomass can be used for coal substitution in the production of electrical energy. [Projekat Ministarstva nauke Republike Srbije, br. TR 33039

  20. Microseismic Precursory Characteristics of Rock Burst Hazard in Mining Areas Near a Large Residual Coal Pillar: A Case Study from Xuzhuang Coal Mine, Xuzhou, China

    Science.gov (United States)

    Cao, An-ye; Dou, Lin-ming; Wang, Chang-bin; Yao, Xiao-xiao; Dong, Jing-yuan; Gu, Yu

    2016-11-01

    Identification of precursory characteristics is a key issue for rock burst prevention. The aim of this research is to provide a reference for assessing rock burst risk and determining potential rock burst risk areas in coal mining. In this work, the microseismic multidimensional information for the identification of rock bursts and spatial-temporal pre-warning was investigated in a specific coalface which suffered high rock burst risk in a mining area near a large residual coal pillar. Firstly, microseismicity evolution prior to a disastrous rock burst was qualitatively analysed, and the abnormal clustering of seismic sources, abnormal variations in daily total energy release, and event counts can be regarded as precursors to rock burst. Secondly, passive tomographic imaging has been used to locate high seismic activity zones and assess rock burst hazard when the coalface passes through residual pillar areas. The results show that high-velocity or velocity anomaly regions correlated well with strong seismic activities in future mining periods and that passive tomography has the potential to describe, both quantitatively and periodically, hazardous regions and assess rock burst risk. Finally, the bursting strain energy index was further used for short-term spatial-temporal pre-warning of rock bursts. The temporal sequence curve and spatial contour nephograms indicate that the status of the danger and the specific hazardous zones, and levels of rock burst risk can be quantitatively and rapidly analysed in short time and in space. The multidimensional precursory characteristic identification of rock bursts, including qualitative analysis, intermediate and short-time quantitative predictions, can guide the choice of measures implemented to control rock bursts in the field, and provides a new approach to monitor and forecast rock bursts in space and time.

  1. Lignite; Braunkohle

    Energy Technology Data Exchange (ETDEWEB)

    Kaltenbach, Erwin; Maassen, Uwe [Debriv e.V., Berlin und Koeln (Germany)

    2015-07-01

    The domestic lignite is the most important and in the foreseeable future, the only domestic energy resource that is available in large quantities and economically. It makes an essential contribution to secure and competitive energy supply and has a high regional as macroeconomic importance. The required guarantied capacity for the development of renewable energy, the lignite provides under competition conditions. The flexibility of the lignite power plants is in addition to security of supply and competitiveness, a strategic added value for a reliable power supply. [German] Die heimische Braunkohle ist die wichtigste und in ueberschaubarer Zukunft auch die einzige heimische Energieressource, die in grossen Mengen und wirtschaftlich zur Verfuegung steht. Sie leistet einen unverzichtbaren Beitrag zur sicheren und wettbewerbsfaehigen Energieversorgung und hat eine hohe regional- wie gesamtwirtschaftliche Bedeutung. Die fuer den Ausbau der erneuerbaren Energien notwendige gesicherte Leistung stellt die Braunkohle unter Wettbewerbsbedingungen zur Verfuegung. Die Flexibilitaet des Braunkohlenkraftwerksparks ist neben Versorgungssicherheit und Wettbewerbsfaehigkeit ein strategischer Zusatznutzen fuer eine sichere Stromversorgung.

  2. Histopathological alterations of the gills, liver and kidneys in Anabas Testudineus (Bloch) fish living in an unused lignite mine, Li District, Lamphun Povince, Thailand

    Energy Technology Data Exchange (ETDEWEB)

    Saenphet, S.; Thaworn, W.; Saenphet, K. [Chiang Mai University, Chiang Mai (Thailand). Faculty of Science

    2009-09-15

    The acidity of mine water generally makes it toxic to most organisms. The gills, kidneys and livers of Anabas testudineus Bloch fish inhabiting the acidic water (pH 2-4) of an unused lignite mine in Li District, Lamphun Province, Thailand were examined and compared to those of farmed fish. Tissue abnormalities were found in all investigated organs. Deterioration and telangiectasia of gill filaments were found. Liver tissue revealed hemorrhages, blood congestion and necrotic cells with mononuclear cell infiltration. In addition, hypertrophy of the epithelial cells of the renal tubules with reduced lumens, aneurisms of the renal tubules, and contractions of the glomeruli in the Bowman's capsule were observed. These histopathological findings suggest the acidic water in this habitat causes severe damage to the internal organs of fish and consequently alter their physiological status. Since the water in this pond is utilized by local people, these findings highlight the need for adequate water treatment.

  3. Lignite As Contributory Factor to Regional Development of Greece

    OpenAIRE

    Ilias Kordas

    2006-01-01

    Lignite (brown coal) is Greece's most important energy mineral raw material. Lignite exploitation has made a highly significant contribution to the development of energy sector of Greece on past 50 years, and will, according to estimations, continue to supply energy for another 40 years. Greece is very rich in Lignite resources. The two main basins - from where Lignite is extracted by opencast mining - are a) in Western Macedonia (northen Greece) where is generated the 70% of the whole electr...

  4. 30 CFR 75.207 - Pillar recovery.

    Science.gov (United States)

    2010-07-01

    ... SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.207 Pillar recovery. Pillar recovery shall be... be left in place. (b) Before mining is started in a pillar split or lift— (1) At least two rows of breaker posts or equivalent support shall be installed— (i) As close to the initial intended breakline as...

  5. Modeling stress–strain state of rock mass under mining of complex-shape extraction pillar

    Science.gov (United States)

    Fryanov, VN; Pavlova, LD

    2018-03-01

    Based on the results of numerical modeling of stresses and strains in rock mass, geomechanical parameters of development workings adjacent to coal face operation area are provided for multi-entry preparation and extraction of flat seams with production faces of variable length. The negative effects on the geomechanical situation during the transition from the longwall to shortwall mining in a fully mechanized extraction face are found.

  6. Further validation of bracket pillar design methodology

    CSIR Research Space (South Africa)

    Vieira, F

    1998-07-01

    Full Text Available Design charts for bracket pillar design were developed under a previous SIMRAC project GAP 223 to provide rock mechanics engineers with an initial estimate of bracket pillar sizes for clearly identified geological discontinuities, based on mining...

  7. Measurement of sub-surface strata behaviour in bord and pillar mining: a case study

    International Nuclear Information System (INIS)

    Krishna, R.

    1991-01-01

    Ranigunj coalfield (India) has been facing significant problems due to subsidence as a result of underground mining of coal seams. The occurrence of the thick seams in close proximity, shallow depth, great variation in the nature of superincumbent strata from site to site, followed by the slow rate of extraction, has aggravated subsidence problems. In the recent past, many such workings have collapsed, damaging a large number of surface structures. In view of the aforesaid need, a comprehensive project financed by the Ministry of Energy (Coal), was undertaken by the Department of Mining Engineering, Indian Institute of Technology, Kharagpur, at a Colliery in Ranigunj Coalfield. This investigation revealed that the caving horizon occurred at 4 times the extracted seam height, which differs from the findings in the UK, USA, and Australia. Also, it appears possible to estimate strata displacements from geological and physicomechanical information from the overlying rocks using the bending moment principle. Further, it was observed that the shallow workings could give rise to a sink hole type of subsidence, which is dangerous and could adversely affect the environment, safety of the public and properties. 11 refs., 13 figs., 1 tab

  8. Source apportionment by PMF on elemental concentrations obtained by PIXE analysis of PM10 samples collected at the vicinity of lignite power plants and mines in Megalopolis, Greece

    International Nuclear Information System (INIS)

    Manousakas, M.; Diapouli, E.; Papaefthymiou, H.; Migliori, A.; Karydas, A.G.; Padilla-Alvarez, R.; Bogovac, M.; Kaiser, R.B.; Jaksic, M.; Bogdanovic-Radovic, I.; Eleftheriadis, K.

    2015-01-01

    Particulate matter (PM) is an important constituent of atmospheric pollution especially in areas under the influence of industrial emissions. Megalopolis is a small city of 10,000 inhabitants located in central Peloponnese in close proximity to three coal opencast mines and two lignite fired power plants. 50 PM 10 samples were collected in Megalopolis during the years 2009–11 for elemental and multivariate analysis. For the elemental analysis PIXE was used as one of the most effective techniques in APM analytical characterization. Altogether, the concentrations of 22 elements (Z = 11–33), whereas Black Carbon was also determined for each sample using a reflectometer. Factorization software was used (EPA PMF 3.0) for source apportionment analysis. The analysis revealed that major emission sources were soil dust 33% (7.94 ± 0.27 μg/m 3 ), biomass burning 19% (4.43 ± 0.27 μg/m 3 ), road dust 15% (3.63 ± 0.37 μg/m 3 ), power plant emissions 13% (3.01 ± 0.44 μg/m 3 ), traffic 12% (2.82 ± 0.37 μg/m 3 ), and sea spray 8% (1.99 ± 0.41 μg/m 3 ). Wind trajectories have suggested that metals associated with emission from the power plants came mainly from west and were connected with the locations of the lignite mines located in this area. Soil resuspension, road dust and power plant emissions increased during the warm season of the year, while traffic/secondary, sea spray and biomass burning become dominant during the cold season

  9. Source apportionment by PMF on elemental concentrations obtained by PIXE analysis of PM10 samples collected at the vicinity of lignite power plants and mines in Megalopolis, Greece

    Science.gov (United States)

    Manousakas, M.; Diapouli, E.; Papaefthymiou, H.; Migliori, A.; Karydas, A. G.; Padilla-Alvarez, R.; Bogovac, M.; Kaiser, R. B.; Jaksic, M.; Bogdanovic-Radovic, I.; Eleftheriadis, K.

    2015-04-01

    Particulate matter (PM) is an important constituent of atmospheric pollution especially in areas under the influence of industrial emissions. Megalopolis is a small city of 10,000 inhabitants located in central Peloponnese in close proximity to three coal opencast mines and two lignite fired power plants. 50 PM10 samples were collected in Megalopolis during the years 2009-11 for elemental and multivariate analysis. For the elemental analysis PIXE was used as one of the most effective techniques in APM analytical characterization. Altogether, the concentrations of 22 elements (Z = 11-33), whereas Black Carbon was also determined for each sample using a reflectometer. Factorization software was used (EPA PMF 3.0) for source apportionment analysis. The analysis revealed that major emission sources were soil dust 33% (7.94 ± 0.27 μg/m3), biomass burning 19% (4.43 ± 0.27 μg/m3), road dust 15% (3.63 ± 0.37 μg/m3), power plant emissions 13% (3.01 ± 0.44 μg/m3), traffic 12% (2.82 ± 0.37 μg/m3), and sea spray 8% (1.99 ± 0.41 μg/m3). Wind trajectories have suggested that metals associated with emission from the power plants came mainly from west and were connected with the locations of the lignite mines located in this area. Soil resuspension, road dust and power plant emissions increased during the warm season of the year, while traffic/secondary, sea spray and biomass burning become dominant during the cold season.

  10. Overview of Neyveli lignite complex

    Energy Technology Data Exchange (ETDEWEB)

    1984-09-01

    The growth and development of the Neyveli lignite complex in Tamil Nadu, India are discussed. A second lignite mine is being developed together with a second thermal power station and erection of transmission lines between Neyveli-Salem and Neyveli-Red Hills is under way. The contribution of power to Tamil Nadu has grown into an extremely valuable asset; exports have risen by 71% in the four years leading up to 1984 and company turn-over has increased 164% over the same period. Performance during 1983-84 is analysed in terms of production figures, productivity and capacity utilisation.

  11. Laboratory experiments and analytical investigations on the transfer of organic substances from lignite into ground water and residue lakes during flooding of opencast lignite mines. Final report; Laborexperimente und analytische Untersuchungen ueber den Eintrag braunkohlebuertiger organischer Stoffe in Grundwaesser und Restseegewaesser bei der Flutung von Braunkohletagebauen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Herzschuh, R.; Frauendorf, H.; Herrmann, D.; Pietzsch, K.

    2000-05-01

    Lignite samples of diffrent lithotypes and composition from opencast mines of Lusatia and the region near Leipzig were submitted to weathering processes in laboratory scale experiments and the transfer of organic matter from lignite into the hydrosphere has been observed. By means of high-performance liquid chromatography/electrospray mass spectrometry used in combination with data from gas chromatography/mass spectrometry numerous lignite-derived aromatic and heteroaromatic (poly-)carboxylic acids as well as aliphatic dicarboxylic acids could be characterized in the aqueous extracts. Investigations on water samples from lignite mining residue lakes cofirm these results. Furthermore, formation of chlororganic compounds like polychlorinated dibenzo-p-dioxine and furans (PCDD/F) and polychlorinated biphenyls (PCB), benzenes (PCBz) and phenols (PCPh) has been investigated on different lignite samples under natural weathering conditions and thermal treatment. (orig.) [German] Braunkohlen verschiedener Lithotypen und Zusammensetzung aus Tagebauen der Lausitz und der Region um Leipzig wurden in Laborexperimenten Verwitterungsprozessen unterzogen und der Uebergang organischer Materie aus der Braunkohle in die Hydrosphaere beobachtet. Mit Hilfe der HPLC-Elektrospray-MS-Untersuchungen in Kombination mit Daten aus GC-MS-Messungen konnten zahlreiche aus der Braunkohle stammende aromatische und heteroaromatische (Poly-)Carbonsaeuren sowie aliphatische Dicarbonsaeuren in den waessrigen Extrakten charakterisiert werden. Untersuchungen an Wasserproben aus bereits gefluteten Tagebaurestseen bestaetigen diese Ergebnisse. Weiterhin wurde die Bildung chlororganischer Verbindungen, wie polychlorierter Dibenzo-p-dioxine und -furane (PCDD/F) sowie polychlorierter Biphenyle (PCB), Benzole (PCBz) und Phenole (PCPh) an unterschiedlichen Braunkohleproben unter natuerlichen Bedingungen und nach thermsicher Behandlung untersucht. (orig.)

  12. The future path of lignite production in the Balkan countries

    International Nuclear Information System (INIS)

    Boussios, E.; Koikouzas, N.K.

    1997-01-01

    The future development of the European Union and Balkan lignite industry is examined in this paper. Lignite in some countries represents for the last decade by far the most important fuel for electricity generation. The economically recoverable lignite reserves of the Balkans (21.36 x 10 9 t) and Greece (4.0 x 10 9 t) are sufficient to meet their energy demand for the next decades (50-100 years). The Balkan countries intended to increase their lignite production, in the near future, as result of the increase of their primary energy demand and their efforts to meet their energy requirements by using domestic resources. Greece also plans to increase lignite production. On the contrary, the remaining of the European Union countries intend to decrease their lignite production. Nevertheless, the countries of Balkan region which are presently in a transition period to the market economy, have to deal with a decrease of people employed in the lignite mining industry. However, Balkan region seems to be the most promising area for the future development of the lignite industry in the enlarged EU, after making the following alterations in the lignite sector: Rehabilitation of the lignite open-pit mines, closure of the most underground mines, privatization of the most prosperous mines, modification of the existing technology, introduction of the 'clean' coal technology, etc. New opportunities for the development and modernization of the lignite industry in Balkan countries arise, after their possible entrance into the European Union, considering also that lignite is one of their most important indigenous energy source. For the necessary modernization of the lignite industry, development of collaborations for the capital and know-how transferring is required. (Author)

  13. The Effect of Mining Activity on the Occurrence of Mining Tremors in the Safety Shaft Pillar of the Kladno-Mayrau Coal Mine

    Czech Academy of Sciences Publication Activity Database

    Živor, Roman; Buben, Jiří

    16(118) (2000), s. 203-214 ISSN 1211-1910 R&D Projects: GA ČR GA105/96/1065 Institutional research plan: CEZ:AV0Z3046908 Keywords : tremor s * drifting * extraction Subject RIV: DH - Mining, incl. Coal Mining

  14. Impact of biocrust succession on water retention and repellency on open-cast lignite mining sites under reclamation in Lower Lusatia, NE-Germany

    Science.gov (United States)

    Gypser, Stella; Fischer, Thomas; Lange, Philipp; Veste, Maik

    2016-04-01

    Mining activities can strongly affect ecosystem properties by destruction of naturally developed soils and removal of vegetation. The unstructured substrates show high bulk densities, compaction, low water infiltration rates, reduced water holding capacities and higher susceptibility to wind and water erosion. In the initial stage of the ecosystem development, the post-mining sites are open areas without or with a low cover of higher vegetation. It is well-known that biocrusts are able to colonize the soil surface under such extreme conditions without human support and affect soil hydrological processes such as water infiltration, run-off or re-distribution. Investigations were conducted on two former lignite open-cast mining sites, an artificial sand dune on the reclaimed watershed Welzow "Neuer Lugteich" and a reforestation area in Schlabendorf (Brandenburg, north-east Germany). The aim was to relate the hydrological characteristics of the topsoil to successional stages of biological soil crusts on reclaimed soils and their influence on repellency index and water holding capacity compared to pure mining substrate. Our study emphasized the influence of changing successional stages and species composition of biological soil crusts, forming a small-scale crust pattern, on water repellency and retention on sandy soils in temperate climate. Different successional stages of soil crusts were identified from initial scattered green algae crusts, dominated by Zygogonium spec. and Ulothrix spec., and more developed soil crusts containing mosses such as Ceratodon purpureus and Polytrichum piliferum. Lichens of the Genus Cladonia were more pronouncedly contributed to biocrusts at later and mature stages of development. The repellency index on the one hand increased due to the cross-linking of sand particles by the filamentous green algae Zygogonium spec. which resulted in clogging of pores, and on the other hand decreased with the occurrence of moss plants due to absorption

  15. Coal pillar design procedures

    CSIR Research Space (South Africa)

    York, G

    2000-03-01

    Full Text Available Final Project Report Coal pillar design procedures G. York, I. Canbulat, B.W. Jack Research agency: CSIR Mining Technology Project number: COL 337 Date: March 2000 2 Executive Summary Examination of collapsed pillar cases outside of the empirical... in strength occurs with increasing specimen size. 45 40 35 30 25 20 15 10 5 0 20 40 60 80 100 120 140 160 UNIAX IA L COMPR EHEN SIV E S TR ENG TH (M Pa ) CUBE SIZE (cm) Figure 1...

  16. Powerful boost for Indian lignite

    Energy Technology Data Exchange (ETDEWEB)

    1985-06-01

    The Neyveli Lignite Corporation (NLC) of India has begun the first phase of an expansion program that will open a second mine and boost lignite production in Tamil Nadu to nearly five times its present level within the next 15 years. Mining conditions at Neyveli are particularly difficult. The harsh abrasive overburden strata present severe and strenuous conditions; sticky and marshy surface clays, the presence of groundwater aquifers, the cyclonic and monsoonal climate and high stripping ratios are other problems. The overburden is drilled and blasted; in areas of sticky topsoil, non-stick liners for the buckets etc. are used. Adequate safeguards and infrastructure are being developed to deal with differing strata conditions. The conveyor transport system features slow, wider belt conveyors, changeover from fixed type roller to freely hanging garland type, interlinking of benches and specially designed drive heads. The groundwater aquifers are continuously depressurized by grid pumping from a series of pumps; boreholes have been sunk to 120 m.

  17. Silicified conifer forests and potential mining problems in seam M2 of the Gore Lignite Measures (Miocene), Southland, New Zealand

    Energy Technology Data Exchange (ETDEWEB)

    Lindqvist, J K; Isaac, M J [New Zealand Geological Survey, Dunedin (New Zealand). Dept. of Scientific and Industrial Research

    1991-04-01

    Silicified conifer ({ital Podocarpus cf. hallii}) stumps up to 0.8 m in diameter are present at two levels in seam M2 of the Miocene Gore Lignite Measures, Mataura Coalfield, eastern Southland. The in situ stumps are believed to be the remains of forests which grew during pauses in peat accumulation, when groundwater levels were depressed as a result of climatic change or local basinal processes. Growth-ring measurements show the trees increased in radius between 0.16 and 1 mm per year. In two of six specimens, the growth-rates halved during their final 30-40 years of life; rising water levels may have resulted in less favourable growth conditions. Within the stumps, much of the wood structure is well preserved. Progressive diagenesis involved impregnation of the cell walls by silica, infilling of the cell lumens with length-slow chalcedony and opaline silica, and deposition of opal, length-fast chalcedony, and minor siderite in fractures. Radial and axial parenchyma contain coalified organic material and minor chalcedony. Filaments of wood-rotting fungi and probable root masses of epiphytes are present in some fossil wood. However, by analogy with modern Podocarpus hallii, the stumps were probably preserved for later silicification because the wood was highly resistant to fungal and bacterial decay. The stumps presumably functioned as conduits to ascending silica-saturated meteoric groundwater and water released during compaction, because of the contrasts in permeability between the vertical stumps and the surrounding peat. 25 refs., 12 figs.

  18. Ecotoxicological relations on a large pig fattening farm located in a lignite mining area and near a solid fuel power plant

    Energy Technology Data Exchange (ETDEWEB)

    Raszyk, J.; Docekalova, H.; Rubes, J.; Gajduskova, V.; Masek, J.; Rodak, L.; Bartos, J. (Veterinary Research Institute, Brno (Czechoslovakia))

    1992-01-01

    Major contaminants identified in 1983-1984 on a pig fattening farm located in a lignite mining area and near a solid fuel power plant, were mercury, cadmium, lead, chromium and aflatoxin B1. Feed samples were collected to assess the contamination load at feed uptake. Permissible concentrations of mercury, chromium, cadmium, aflatoxin B1, lead and atrazin in the feed were exceeded in 56, 50, 31, 19, 6 and 6% samples, respectively. Permissible concentrations of mercury, cadmium and lead in porcine muscles were exceeded in 65, 51, 24% samples, respectively. Pigs fattened in the contaminated environment (i.e. fed contaminated feed mixtures, inspiring contaminated dust and absorbing percutaneously contaminants from dust deposits on the body surface) showed: (1) impairment of the genetic apparatus; (2) a certain degree of immunosuppression; (3) higher feed consumption per 1 kg weight gain and lower average daily weight gain; (4) increased incidence of health disorders. The authors were not allowed to analyse ash and solid emissions from the power plant. Therefore the share of the emissions in the overall environmental contamination on the fattening farm could not be quantified. The personnel, working in the contaminated environment for a prolonged period, are endangered most of all by stable dust, being exposed to its mechanical, chemical, allergic and infectious effects. Consumption of meat and organs from pigs fattened in a contaminated environment is associated with the risk of an increased uptake of various contaminants.

  19. Seasonal variations of natural radionuclides, minor and trace elements in lake sediments and water in a lignite mining area of North-Western Greece.

    Science.gov (United States)

    Noli, Fotini; Tsamos, Panagiotis

    2018-05-01

    The radiological and chemical pollution of a cluster of four lakes in a lignite mining area of North-Western Greece was investigated using a variety of analytical techniques. Alpha spectrometry was applied to measure the activity concentrations of the uranium radioisotopes (U-234, U-235, and U-238) in waters. The mass activities of U-238, Th-232, and K-40 in sediments were measured by high-resolution gamma spectrometry. Furthermore, the determination of the minor and trace elements was carried out by instrumental neutron activation analysis (INAA) in both water and sediments samples, respectively. Pollution levels were also evaluated by calculating enrichment factors (EFs), contamination factors (CFs) and pollution load index (PLI). The data were discussed taking into account several parameters such as the distance from the pollution source, temperature, and location and showed that the environmental impact in this region could not be considered as negligible. The deviation of the isotopic ratio of U-234/U-238 from the equilibrium value indicated waters with intensive dissolution of uranium. The activity values in both waters and sediments found to be low in cool periods and increased in warm periods. Moreover, the concentrations of the elements U, Zn, and Fe were raised in water samples indicating possible pollution as well as the CFs and PLI denoted accumulation in the sediments and moderate to severe contamination for Zn and Cr in some cases.

  20. A physical and numerical modelling investigation of the roadway stability in longwall mining, with and without narrow pillar protection

    Energy Technology Data Exchange (ETDEWEB)

    Yavuz, H.; Fowell, R.J. [Suleyman Demirel University, Isparta (Turkey)

    2004-03-01

    The drivage of the supply gate of a development panel in the presumed low stress zone adjacent to the loader gate of an excavated panel with a very small width of intervening pillar between the two entries, known as skin-to-skin working, resulted in an extensive fall of the supply gate roof at Bilsthorpe colliery in 1993. This fall left a question over the application of skin-to-skin drivage of gate entries supported primarily by rock bolts. To investigate the possible reasons behind this fall, both physical and numerical modelling studies were carried out. Physical and numerical models were successful in demonstrating the potential danger of the working method with the rock bolt support system employed. Development of a shear failure plane from the rib edge into roof strata of the loader gate and development of the second shear failure plane at the abutment side of the supply gate exposed the supply gate to the fall of large rock blocks released by shear failure zones. Models demonstrated that the fall of the supply gate roof was not due to the inability of the rock bolts to prevent bed separation, but it was the method of working that made the bolts ineffective due to the height of the block delineated by the shear failure planes. Further physical and numerical models were undertaken to investigate the influence of 5, 7.5 and 10 in wide intervening pillars between the entries on the stability of the rock bolt supported supply gate roof. These studies showed that a 7.5 in or 10 in wide pillar would have prevented development of failure zones and fall of the roof while a 5 in pillar was found to be an undersized pillar width causing the development of extensive failure zones in the roof.

  1. Iron precipitations in the Lusatian lignite district. Pt. 1: water pumpage and water drainage in the opencast mine of Nochten, hydrochemistry of mine water; Eisenausfaellungen im Lausitzer Braunkohlerevier. T. 1: Wasserhebung und -ableitung im Tagebau Nochten, Hydrochemie der Suempfungswaesser

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, I. [LAUBAG, Senftenberg (Germany); Uhlmann, W. [IWB - Institut fuer Wasser und Boden, Dresden (Germany)

    2002-09-01

    Opencast lignite mines are subject to permanent drainage. Due to iron disulphide weathering, drainage waters are acidic and rich in ferrous iron and sulphate. In the case of the mine Nochten (Lusatia, East Germany) the originating water is directed from the mine through several open ditches and finally through a pipeline to reach to purification plant at a distance of 14 km. During this course part of the ferrous iron is oxidised to form ferric iron, which precipitates as Fe(III)-minerals. The iron loss in the drainage system between the open cast Nochten to the purification plant Schwarze Pumpe is 30-37% under summer conditions and 18% under winter conditions. Especially for the pipeline these precipitates represent a serious problem, as they result in incrustations and therefore in decreased discharge rates. This article focuses on the hydrochemical processes occurring during the discharge of water to the purification plant. Investigations were based on hydrochemical measurements in the drainage systems as well as on laboratory experiments on the oxidation kinetics of ferrous iron. These resulted in the following findings: (1) The oxidation of ferrous iron in the acidic waters is slow even at oxygen concentrations near saturation. Thus, oxygen is not the limiting factor for the oxidation process. (2) Oxidation kinetics are strongly dependent on temperature. Conclusively, a reduction of iron precipitates may be achieved firstly by shortening the distance of the transport course and secondly by preventing a warming up of waters in summer. (orig.)

  2. From deposit modelling to the mine plan engineering guidance in a Greenfield project for the opening of a lignite open-cast mine during the preparation and development phase

    International Nuclear Information System (INIS)

    Hertling, H.

    2010-01-01

    In order to supply the nearby power plant Elbistan B, a new open-cast mine is being developed at the Collolar Field in Turkey. Initial fieldwork began in mid-2007, followed by overburden removal in early 2008 and lignite production in 2009. Several planning studies have been undertaken in order to prepare and undertake the initial work in just under two years, including the establishment of a geological model as a basis for calculating reserves, and for hydrological and geotechnical calculations, leading to a drainage concept and the formulation of requirements made on the slope stability. This paper presented the framework concept for the modelling and discussed the geological modelling and selection of a suitable development plan. The hydrological calculations and planning of drainage measures were also outlined. The more detailed plans for phase two, including the database for hydro-geological modelling, pumping tests and laboratory tests, ground water modelling, and the dewatering concept were also presented. The paper also discussed the determination of geotechnical parameters, calculation methods, and the slope stabilities at the mining and dumping site. It was concluded that regular comparison to plans and calculations on drainage and slope stability must be conducted when planning and operating a mine. 3 figs.

  3. Solubilization of Australian lignites by fungi and other microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Catcheside, D.E.A.; Mallett, K.J. (Flinders University, Bedford Park, SA (Australia). School of Biological Sciences)

    Lignites (brown coals) from the Latrobe Valley in Victoria are solubilized by {ital Coriolus versicolor}, {ital Phanerochaete chrysosporium}, and five other species known to be active on Leonardite and various acid-treated North America lignites. Run-of-mine coal from Morwell and Loy Yang is refractory but is soluble after pretreatment with acid. A weathered deposit at Loy Yang, like Leonardite, is susceptible to biosolubilization without pretreatment. The white rot fungi {ital Ganoderma applanatum}, {ital Perenniporia tephropora} ({ital Fomes lividus}), {ital Pleurotus ostreatus}, {ital Pycnoporus cinnabarinus}, {ital Rigidoporus ulmarius}, and {ital Xylaria hypoxylon} were found to be capable of solubilizing lignite. In contrast, brown rot fungi were weakly active or inactive under the same test conditions. Lignite-degrading fungi, actinomycetes, and other bacteria, including some active on untreated run-of-mine coal, were isolated from natural lignite exposures and mining sites. 15 refs., 5 tabs.

  4. Soil algae in brown coal and lignite post-mining areas in central Europe (Czech Republic and Germany)

    Czech Academy of Sciences Publication Activity Database

    Lukešová, Alena

    2001-01-01

    Roč. 9, č. 4 (2001), s. 341-350 ISSN 1061-2971 R&D Projects: GA MŠk ME 076 Institutional research plan: CEZ:AV0Z6066911 Keywords : algae * cyanobacteria * coal mining Subject RIV: EH - Ecology, Behaviour Impact factor: 1.011, year: 2001

  5. Technology and use of lignite. Proceedings of the tenth biennial lignite symposium

    Energy Technology Data Exchange (ETDEWEB)

    Kube, W. R.; Gronhovd, G. H. [comps.

    1979-01-01

    The symposium on the technology and use of lignite was sponsored by the US Department of Energy and the University of North Dakota, and held at Grand Forks, North Dakota, May 30-31, 1979. Twenty-one papers from the proceedings of this tenth biennial lignite symposium have been entered into EDB and ERA and three also into EAPA. The papers discuss lignite deposits in the USA, mining plans, gasification and in-situ gasification, and combustion in fossil-fuel power plants. (LTN)

  6. Overburden of lignite mining pits. A problem for the future?; Abraumkippen des Braunkohlenbergbaus. Ein Problem fuer die Zukunft?

    Energy Technology Data Exchange (ETDEWEB)

    Cremer, Nils [Erftverband, Bergheim (Germany); Huesener, Dirk [Landesamt fuer Natur, Umwelt und Verbraucherschutz NRW, Recklinghausen (Germany)

    2009-07-01

    Due to the brown coal mining industry, overburden dumps with a total area of approximately 300 square kilometers will develop at the Niederrhein (Federal Republic of Germany) up to the year 2045. The renewed rise of the lowered ground-water level will rise in high sulfate loadings in the next decades. The expected propagation of the registered materials already today is of great interest for long-term water-economical planning.

  7. Development of an on-line coal quality management system in a lignite open pit mine in Serbia

    Energy Technology Data Exchange (ETDEWEB)

    Zimmer, B. [Montan Bildungs-und Entwicklungsgesellschaft mbH, Theiben, (Germany)

    2010-07-01

    This paper presented a study regarding the development of a coal quality management system (CQMS) for two open pit mines located in Serbia called Tamnava West and Veliki Crljeni. The study was based on on-line measurements, and was commissioned by the public energy corporation Elektroprivreda Srbjie. The purpose of the study was to develop a CQMS that met the quality requirements of the power plants by implementing a rigorous exploration, production planning, and production monitoring system in order to control the production according to certain quality parameters. The paper provided general information and described the initial situation. It also presented an analysis of the necessity to introduce a production monitoring and control system. The setup and layout of a production monitoring and control system based on on-line measurements were outlined, with particular reference to the determination of input parameters for every excavator for the tracking of masses; the simulation of mass tracking and summation of the masses at the transfer points towards the major conveyor; and the monitoring of the output and control of the mass flow according to determined limit values. Recommendations for implementation were also discussed. It was concluded that the newly developed CQMS at Tamnava West open pit mine could be classified as uncomplicated with regard to the quality parameters to be controlled, since currently only calorific value was being controlled. 5 refs., 8 figs.

  8. Long-term effects of deep soil loosening on root distribution and soil physical parameters in compacted lignite mine soils

    Science.gov (United States)

    Badorreck, Annika; Krümmelbein, Julia; Raab, Thomas

    2015-04-01

    Soil compaction is a major problem of soils on dumped mining substrates in Lusatia, Germany. Deep ripping and cultivation of deep rooting plant species are considered to be effective ways of agricultural recultivation. Six years after experiment start, we studied the effect of initial deep soil loosening (i.e. down to 65 cm) on root systems of rye (Secale cereale) and alfalfa (Medicago sativa) and on soil physical parameters. We conducted a soil monolith sampling for each treatment (deep loosened and unloosened) and for each plant species (in three replicates, respectively) to determine root diameter, length density and dry mass as well as soil bulk density. Further soil physical analysis comprised water retention, hydraulic conductivity and texture in three depths. The results showed different reactions of the root systems of rye and alfalfa six years after deep ripping. In the loosened soil the root biomass of the rye was lower in depths of 20-40 cm and the root biomass of alfalfa was also decreased in depths of 20-50 cm together with a lower root diameter for both plant species. Moreover, total and fine root length density was higher for alfalfa and vice versa for rye. The soil physical parameters such as bulk density showed fewer differences, despite a higher bulk density in 30-40cm for the deep loosened rye plot which indicates a more pronounced plough pan.

  9. Develop guidelines for the design of pillar systems for shallow and intermediate depth, tabular, hard rock mines and provide methodology for assessing hangingwall stability and support requirements for the panels between pillars

    CSIR Research Space (South Africa)

    Haile, AT

    1995-12-01

    Full Text Available The overall view of the research being conducted at Impala platinum was to improve pillar design techniques through a rock testing programme, underground instrumentation and back analysis. The laboratory rock testing programme has provided a useful...

  10. Application of a routine moment tensor inversion capability in the development of a new design consideration for the stability of foundations of stabilising pillars in deep level gold mines and pillars in intermediate depth hard rock mines

    CSIR Research Space (South Africa)

    Linzer, LM

    2002-03-01

    Full Text Available analysis of failure mechanisms, development of moment tensor inversion program and verification of the hybrid moment tensor inversion technique. Geomechanical and geotechnical analyses were undertaken to determine the rock mass condition of in situ... on the mine using the ISS software and then reprocessed using AURA, the seismogram processing analysis program written by CSIR Miningtek. It was found that the magnitudes computed using AURA were substantially larger than those computed using the ISS...

  11. Degradation/solubilization of Chinese lignite by Penicillium sp. P6

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, H.L.; Yang, J.S.; Wang, F.Q.; Chen, W.X. [China Agricultural University, Beijing (China). Key Laboratory of Agro-Microbial Resource and Application, Ministry of Agrio, College of Biological Science

    2006-01-15

    Penicillium sp. P6, isolated from coal mine soil at the Qiantong colliery Liaoning Province, Northeast China, can degrade Chinese lignite in 36 h on a plate colony and in 48 h using a 4-day cultured cell-free filtrate. Results of elemental analysis and IR spectrometry indicated that solubilized products exhibited some alterations in comparison to the original lignite. The amount of fulvic acid extracted from the biodegraded lignite was high, and the molecular distribution of the humic acids from biodegraded lignite changed distinctively in comparison to which extracted from the control lignite, possibly due to the depolymerization associated with fungal biodegradation.

  12. The thar lignite project in the Sindh province, Pakistan

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, L. [RWE Power International, RE GmbH, Mining Dept., Koeln (Germany); Dittrich, W. [RWE Power International, RE GmbH, Mechanical and Electrical Dept., Koeln (Germany)

    2005-05-01

    A prospective area of the known lignite deposit located in the Thar region was investigated with regard to the future development of an opencast mine. For this purpose, a bankable feasibility study was prepared that evaluates all relevant facts and additional exploration activities. The study includes among others: Geological report; Opencast mine planning; Equipment and infrastructure planning; Assessment of staff requirements; Conceptual design of the power station; Anticipation of environmental aspects; Bankable costing for lignite mining and power generation. In conclusion, the development of an opencast mine and the construction of a 1000 MW power station are feasible in technical and economic terms. For the mine, the shovel/truck method was proposed since it offers cost advantages. For the power station, a closed cooling circuit and pre-drying of the lignite was recommended due to water shortage in the Thar desert. The resulting prices for power generation are usual market costs in Pakistan. (orig.)

  13. Assessment of landslide hazards in a mining area on the example of the Jastrzebie town safety pillar

    Energy Technology Data Exchange (ETDEWEB)

    Rybicki, S; Krokoszynski, P

    1986-01-01

    Evaluates landslide hazards in areas influenced by underground mining with caving or stowing. Effects of ground subsidence and deformation on water conditions and moisture content in clays are analyzed. Moisture effects on soil cohesion and angle of internal friction are investigated on examples from the Jastrzebie area and from the Donbass in USSR. Effects of moisture content increase on soil behavior in zones of compression and tension are comparatively evaluated. Formation of sliding planes under conditions of moisture content increase in zones influenced by ground subsidence is investigated. In the light of soil property analysis slope stability conditions in the Upper Silesia and Lublin basins are discussed. Slopes in the Jastrzebie area are classified according to landslide hazards considering: angle of slope inclination, height, physical soil properties, moisture content and effects of underground mining. 14 refs.

  14. Examine the criteria for establishing the small span small pillar concept as a safe mining method in deep mines,Volume 1 of 1.

    CSIR Research Space (South Africa)

    De Frey, FSA

    2002-01-01

    Full Text Available with conventional breast panel 38 4.4 Critical evaluation of results 39 4.5 A recommended alternative method 41 4.6 Comparison criteria used as for other layouts 45 4.7 Conclusions and future research needs 47 5 MINE ECONOMICS 48 5.1 Mine economic criteria 48... stream_source_info GAP822.pdf.txt stream_content_type text/plain stream_size 176631 Content-Encoding UTF-8 stream_name GAP822.pdf.txt Content-Type text/plain; charset=UTF-8 Safety in Mines Research Advisory Committee...

  15. Future of lignite resources: a life cycle analysis.

    Science.gov (United States)

    Wang, Qingsong; Liu, Wei; Yuan, Xueliang; Zheng, Xiaoning; Zuo, Jian

    2016-12-01

    Lignite is a low-quality energy source which accounts for 13 % of China's coal reserves. It is imperative to improve the quality of lignite for large-scale utilization. To further explore and analyze the influence of various key processes on the environment and economic costs, a lignite drying and compression technology is evaluated using an integrated approach of life cycle assessment and life cycle costs. Results showed that lignite mining, direct air emissions, and electricity consumption have most significant impacts on the environment. An integrated evaluation of life cycle assessment and life cycle costs showed that the most significant contributor to the environmental impacts and economic costs was the lignite mining process. The impact of transportation and wastewater treatment process on the environment and economic costs was small enough to be ignored. Critical factors were identified for reducing the environmental and economic impacts of lignite drying and compression technology. These findings provide useful inputs for both industrial practice and policy making for exploitation, processing, and utilization of lignite resources.

  16. Role of Neyveli lignite in the energy map of India

    Energy Technology Data Exchange (ETDEWEB)

    Srinivasaraghavan, S

    1984-08-01

    For more than two decades, about 35% of the energy demand of Tamil Nadu, a region of southern India, has been provided by Neyveli Lignite Corporation (NLC). NLC was founded as a company by the Indian government in 1956 and it comprises a lignite mine, a thermal power station, a briquetting and carbonisation plant; a fertilizer plant, a process steam plant, and a clay washing plant. The extent of the Neyveli lignite field, the production capacity of the three mines, and the linkage and utilisation of lignite are all considered. Future perspective plans beyond the seventh five year plan are reviewed. The use of coke and fertilizer by the chemical industries is outlined, and ecology and environmental control are discussed.

  17. Role of Neyveli Lignite in the energy map of India

    Energy Technology Data Exchange (ETDEWEB)

    Srinivasaraghavan, S

    1984-08-01

    The Neyveli Lignite Corporation (NLC), a government undertaking, has played an important role in power generation in the southern region of India by contributing about 35% of the energy consumed in Tamil Nadu for over two decades. Performance at the Neyveli Thermal Power Station demonstrates that it is more advantageous to make additions to thermal generating capacity at Neyvili using lignite. Exploration and development of the mines can support this expansion and make the southern region a nucleus for industrial development. 2 tables.

  18. Lignite in North Dakota

    International Nuclear Information System (INIS)

    Porter, C.R.

    1995-01-01

    The State of North Dakota and the lignite industry are working together in a partnership called the Lignite Research, Development and Marketing Program. The program provides funds and supports activities which: preserve and enhance jobs and lignite production; ensure economic growth, stability and opportunity; and maintain a stable and competitive tax base. Since 1987, 70 grants totaling $24 million have been awarded. Each program dollar has resulted in nearly five of matching dollars. These program investments have yielded returns for the state and industry, including an additional $20 million annually from by-products at the Great Plains Synfuels Plant; about $1 million annually from improved reclamation practices; and combustion options, which preserve 2,000 megawatts of existing generation capacity. Research activities have identified future opportunities, including: the SynCoal demonstration plant, requiring 800,000 tons per year of new production; new chemical feedstock by-products from Great Plains worth an additional $26 million annually; revised reclamation practices that could substantially reduce cost; and potential new markets for upgraded lignite of about 12 million tons annually. This program helps ensure a healthy future for the North Dakota lignite industry, which currently represents 10% of the state's total economic base. Such a program is important because it will encourage the development of new and better uses of North Dakota's most abundant resource--lignite coal

  19. Stress-state monitoring of coal pillars during room and pillar extraction

    Czech Academy of Sciences Publication Activity Database

    Waclawik, Petr; Ptáček, Jiří; Koníček, Petr; Kukutsch, Radovan; Němčík, J.

    2016-01-01

    Roč. 15, č. 2 (2016), s. 49-56 ISSN 2300-3960 R&D Projects: GA MŠk(CZ) LO1406; GA MŠk ED2.1.00/03.0082 Institutional support: RVO:68145535 Keywords : stress-state monitoring * room and pillar * coal pillar Subject RIV: DH - Mining , incl. Coal Mining http://www.sciencedirect.com/science/article/pii/S2300396016300180

  20. Slope stability in opencast lignite mining in Spain. Estabilidad de taludes en la mineria de lignito a cielo abierto en Espana

    Energy Technology Data Exchange (ETDEWEB)

    1987-01-01

    The present study assesses the current state of opencast workings in their respective geological and geographical situations and attempts to establish a set of general design criteria for each site according to its location. Six zones were selected in the three principal lignite-producing areas of Spain, two in Galicia - Puentes de Garcia Rodriguez (ENDESA) and Meirama (LIMEISA); three in Teruel - Alloza (ENDESA) Sabina and Yermegada (MFUSA); one in Mallorca - Jupiter (LIGNITOS SA). Two sites not yet in operation were also studied: Barrabasa in Teruel and Lloseta in Mallorca. 60 figs., 25 tabs.

  1. Drying grain using a hydrothermally treated liquid lignite fuel

    Energy Technology Data Exchange (ETDEWEB)

    Bukurov, Z.; Cvijanovic, P.; Bukurov, M. [Univ. of Novi Sad (Yugoslavia); Ljubicic, B.R. [Univ. of North Dakota, Grand Forks, ND (United States)

    1995-12-01

    A shortage of domestic oil and natural gas resources in Yugoslavia, particularly for agricultural and industrial purposes, has motivated the authors to explore the possibility of using liquid lignite as an alternate fuel for drying grain. This paper presents a technical and economic assessment of the possibility of retrofitting grain-drying plants currently fueled by oil or natural gas to liquid lignite fuel. All estimates are based on lignite taken from the Kovin deposit. Proposed technology includes underwater mining techniques, aqueous ash removal, hydrothermal processing, solids concentration, pipeline transport up to 120 km, and liquid lignite direct combustion. For the characterization of Kovin lignite, standard ASTM procedures were used: proximate, ultimate, ash, heating value, and Theological analyses were performed. Results from an extensive economic analysis indicate a delivered cost of US$20/ton for the liquid lignite. For the 70 of the grain-drying plants in the province of Vojvodina, this would mean a total yearly saving of about US $2,500,000. The advantages of this concept are obvious: easy to transport and store, nonflammable, nonexplosive, nontoxic, 30%-40% cheaper than imported oil and gas, domestic fuel is at hand. The authors believe that liquid lignite, rather than an alternative, is becoming more and more an imperative.

  2. Characterization of North American lignite fly ashes. II. XRD Mineralogy

    International Nuclear Information System (INIS)

    McCarthy, G.J.; Johansen, D.M.; Thedchanamoorthy, A.; Steinwand, S.J.; Swanson, K.D.

    1988-01-01

    X-ray powder diffraction has been used to determine the crystalline phase mineralogy in samples of fly ash from each of the lignite mining areas of North America. The characteristic phases of North Dakota lignite fly ashes were periclase, lime, merwinite and the sulfate phases anhydrite, thenardite and a sodalite-structure phase. Mullite was absent in these low-Al/sub 2/O/sub 3/ ashes. Montana lignite ash mineralogy had characteristics of ND lignite and MT subbituminous coal fly ashes; mullite and C/sub 3/A were present and the alkali sulfates were absent. Texas and Louisiana lignite fly ashes had the characteristic mineralogy of bituminous coal fly ash: quartz, mullite, ferrite-spinel (magnetite) and minor hematite. Even though their analytical CaO contents were 7-14%, all but one lacked crystalline CaO-containing phases. Lignite fly ashes from Saskatchewan were generally the least crystalline of those studied and had a mineralogy consisting of quartz, mullite, ferrite spinel and periclase. Quantitative XRD data were obtained. The position of the diffuse scattering maximum in the x-ray diffractograms was indicative of the glass composition of the lignite fly ash

  3. Lignite Fuel Enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Charles Bullinger; Nenad Sarunac

    2010-03-31

    Pulverized coal power plants which fire lignites and other low-rank high-moisture coals generally operate with reduced efficiencies and increased stack emissions due to the impacts of high fuel moisture on stack heat loss and pulverizer and fan power. A process that uses plant waste heat sources to evaporate a portion of the fuel moisture from the lignite feedstock in a moving bed fluidized bed dryer (FBD) was developed in the U.S. by a team led by Great River Energy (GRE). The demonstration was conducted with Department of Energy (DOE) funding under DOE Award Number DE-FC26-04NT41763. The objectives of GRE's Lignite Fuel Enhancement project were to demonstrate reduction in lignite moisture content by using heat rejected from the power plant, apply technology at full scale at Coal Creek Station (CCS), and commercialize it. The Coal Creek Project has involved several stages, beginning with lignite drying tests in a laboratory-scale FBD at the Energy Research Center (ERC) and development of theoretical models for predicting dryer performance. Using results from these early stage research efforts, GRE built a 2 ton/hour pilot-scale dryer, and a 75 ton/hour prototype drying system at Coal Creek Station. Operated over a range of drying conditions, the results from the pilot-scale and prototype-scale dryers confirmed the performance of the basic dryer design concept and provided the knowledge base needed to scale the process up to commercial size. Phase 2 of the GRE's Lignite Fuel Enhancement project included design, construction and integration of a full-scale commercial coal drying system (four FBDs per unit) with Coal Creek Units 1 and 2 heat sources and coal handling system. Two series of controlled tests were conducted at Coal Creek Unit 1 with wet and dried lignite to determine effect of dried lignite on unit performance and emissions. Wet lignite was fired during the first, wet baseline, test series conducted in September 2009. The second test series was

  4. Catalytic cracking of lignites

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, M.; Nowak, S.; Naegler, T.; Zimmermann, J. [Hochschule Merseburg (Germany); Welscher, J.; Schwieger, W. [Erlangen-Nuernberg Univ. (Germany); Hahn, T. [Halle-Wittenberg Univ., Halle (Germany)

    2013-11-01

    A most important factor for the chemical industry is the availability of cheap raw materials. As the oil price of crude oil is rising alternative feedstocks like coal are coming into focus. This work, the catalytic cracking of lignite is part of the alliance ibi (innovative Braunkohlenintegration) to use lignite as a raw material to produce chemicals. With this new one step process without an input of external hydrogen, mostly propylene, butenes and aromatics and char are formed. The product yield depends on manifold process parameters. The use of acid catalysts (zeolites like MFI) shows the highest amount of the desired products. Hydrogen rich lignites with a molar H/C ratio of > 1 are to be favoured. Due to primary cracking and secondary reactions the ratio between catalyst and lignite, temperature and residence time are the most important parameter to control the product distribution. Experiments at 500 C in a discontinuous rotary kiln reactor show yields up to 32 wt-% of hydrocarbons per lignite (maf - moisture and ash free) and 43 wt-% char, which can be gasified. Particularly, the yields of propylene and butenes as main products can be enhanced four times to about 8 wt-% by the use of catalysts while the tar yield decreases. In order to develop this innovative process catalyst systems fixed on beads were developed for an easy separation and regeneration of the used catalyst from the formed char. (orig.)

  5. The development of the Ptolemais lignite deposit, present situation and future perspective of the electrical energy market (Greece)

    International Nuclear Information System (INIS)

    Kavourides, Kostas

    1997-01-01

    PPC is by far the major producer of solid fuels in Greece. Currently the known exploitable reserves of solid fuels, are 4,0 billions tones of lignite and 4 billion cubic meters of peat. Mining of Lignite in Greece started in 1951 at the Aliveri underground mine and was continued at the open cast mines at Ptolemais (1955) and Megalopolis (1919). For more than 45 years. PPC has successfully exploited the Greece Lignite deposit for the production of electricity in order to satisfy the demand in Greece. Today PPC produces 60 million tons of lignite and handles approximately 275 million cubic meters of masses (overburden, lignite and interculated) per year. Lignite is the main energy resource in Greece and its combustion provides 75-80% of the electrical energy consumed in Greece.The Lignite Center of Ptolemais - Amyndeon (LCP-A) operated by the Greece PPC is located in northern Greece, about 110 km west of the city of Thessaloniki. The lignite deposits under exploitation cover an area. of 120 km 2 including 4000 Mt of proven geological reserves and 2700 Mt of exploitable lignite under current economic and technological criteria. Today LCP-A manages six active mines which in 1997 have a rate of handling 245 mil cubic meter of material and producing approx. 48 mil for of lignite. The continuous mining method which employs BWES, conveyors and strackers is the principal mining method used in all the lignite mines at the Ptolemais-Amyndeon Lignite Center. The implementation of selective mining procedures as well as discontinuous and /or combined mining methods differentiates the mining technology at the LCP-A from the respective technology applied in Germany lignite mines. The quality properties suggest that the lignite deposits in Greece are among the world's worst quality deposits exploited for energy production, where approximately 2 kg of lignite are consumed per I kWh of generated power. The main advantages of PPC'S coal orientated development program are the following

  6. Stoichiometric calculations of combustion of Lakhra lignite

    International Nuclear Information System (INIS)

    Ali, I.; Ali, M.M.

    2002-01-01

    Lakhra coal field is largest productive coal field of Pakistan. About 1.5 millions tonne of this coal is, annually, mined and transported daily to various parts of the country in 500 trucks each of 10 tonnes of coal. The major consumers of this coal are brick kilns located in Sindh and Punjab. It is available at Rs. 500/- per tonne at mine head. A number of attempts were made for the production of power (electricity) by foreign companies. Feasibility studies were undertaken but no one set up power plant. It may be due to inferior quality of coal as it is lignitic in nature with high ash and sulfur contents. This coal is also, very sensitive to spontaneous combustion. Spontaneous combustion is the auto-ignition of coal at ambient conditions. Hence there are storage problems. In spite of these drawbacks, a 3(50) Mega Watt (3 units of each 50 mega watt power generation capacity) power plant, based on atmospheric fluidized bed combustion of coal technology (AFBC), was setup in early nineties. The performance of this plant remained poor. The main reasons might be poor quality of coal and limestone. Limestone is used with high sulfur Lakhra lignite, in fluidized bed combustor, to arrest sulfur of the coal, fixing sulfur as calcium sulfate to minimize hazardous emissions of sulfur dioxide (SO/sub 2/). Spontaneous combustion of Lakhra lignite is responsible for each fire of coal and conveyor belt etc. (author)

  7. The effect of lignite quality variation on the efficiency of on-line ash analyzers

    Energy Technology Data Exchange (ETDEWEB)

    Galetakis, Michael J. [Technical University of Crete, Dept. of Mineral Resources Engineering, University Campus, 73 100 Hania (Greece); Pavloudakis, Francis F. [Public Power Corporation SA, General Division of Mines, Kifisou and Dyrrahiou 89, 104 43 Athens (Greece)

    2009-12-01

    A sustainable coal industry needs to achieve a number of objectives including improvements in utilization of deposits, energy efficiency, and environmental performance during combustion. The ''Clean Coal Concept'' promises to combine the secure and low cost electricity supply offered by hard coal and lignite with adequate environmental precautions. In this context, modern quality control systems, which are greatly based on the on-line analyzers, play an important role in achieving sustainability targets. This paper examines the possibility of using commercial on-line analysis systems for monitoring the mineral matter content of low quality lignite mined from the lignite basin of Megalopolis, Peloponnese, Greece. The effect of the accuracy of the on-line analyzers to process control, when used for the characterization of low rank coals with complex and variable composition, is investigated by carrying out numerous bench- and pilot-scale trials. Pilot-scale trials were based on a dual energy gamma-ray transmission analyzer, which was installed on the conveyor belt that transports lignite from the mine pit to the homogenization stockyard. All measurement data were compared to data gathered during the realisation of similar trials in the lignite mines of Ptolemais Basin, Northern Greece. Results indicated that the accuracy of the on-line measurements was not satisfactory and did not allow lignite quality monitoring in real time. The achieved inferior accuracy of the on-line measurement's accuracy, compared to previous applications at other mining sites, was related to the intense variation of the mineral matter content of lignite and lignite composition, which distorted the calibration of the analyzer. The latter is based on certain assumptions regarding the average mass absorption coefficient of the organic and mineral matter contained in the lignite. Further experimental work is needed to investigate solutions for successful implementation of

  8. The origin and distribution of HAPs elements in relation to maceral composition of the A1 lignite bed (Paleocene, Calvert Bluff Formation, Wilcox Group), Calvert mine area, east-central Texas

    Science.gov (United States)

    Crowley, Sharon S.; Warwick, Peter D.; Ruppert, Leslie F.; Pontolillo, James

    1997-01-01

    The origin and distribution of twelve potentially Hazardous Air Pollutants (HAPs; As, Be, Cd, Cr, Co, Hg, Mn, Ni, Pb, Sb, Se, and U) identified in the 1990 Clean Air Act Amendments were examined in relation to the maceral composition of the A1 bed (Paleocene, Calvert Bluff Formation, Wilcox Group) of the Calvert mine in east-central Texas. The 3.2 m-thick A1 bed was divided into nine incremental channel samples (7 lignite samples and 2 shaley coal samples) on the basis of megascopic characteristics. Results indicate that As, Cd, Cr, Ni, Pb, Sb, and U are strongly correlated with ash yield and are enriched in the shaley coal samples. We infer that these elements are associated with inorganic constituents in the coal bed and may be derived from a penecontemporaneous stream channel located several kilometers southeast of the mining block. Of the HAPs elements studied, Mn and Hg are the most poorly correlated to ash yield. We infer an organic association for Mn; Hg may be associated with pyrite. The rest of the trace elements (Be, Co, and Se) are weakly correlated with ash yield. Further analytical work is necessary to determine the mode of occurrence for these elements. Overall, concentrations of the HAPs elements are generally similar to or less than those reported in previous studies of lignites of the Wilcox Group, east-central region, Texas. Petrographic analysis indicates the following ranges in composition for the seven lignite samples: liptinites (5–8%), huminites (88–95%), and inertinites (trace amounts to 7%). Samples from the middle portion of the A1 bed contain abundant crypto-eugelinite compared to the rest of the samples; this relationship suggests that the degradation of plant material was an important process during the development of the peat mire. With the exception of Hg and Mn, relatively low levels of the HAPs elements studied are found in the samples containing abundant crypto-eugelinite. We infer that the peat-forming environment for this

  9. pillared and un-pillared bentonite clays

    African Journals Online (AJOL)

    BARTH EKWUEME

    2011-07-29

    Jul 29, 2011 ... A pseudo-second order kinetic model was used to characterize the metal ion transport ... may endanger human health through consumption of sea food and ... widely reported. The pillared clays are two – dimensional zeolite.

  10. Hydraulic method of working large super-drift pillars

    Energy Technology Data Exchange (ETDEWEB)

    Rad' ko, B.V.; Syroezhkin, P.V.; Durov, V.S.

    1987-03-01

    Describes the method of hydraulic coal extraction introduced in the Pioneer mine belonging to the Dobropol'eugol' coal association. This method was found to reduce the number of collection and ventilation roadways needed significantly, increase their stability, reduce coal loss and increase safety, particularly when mining pillars up to 80 m high. Large scale diagram of hydraulic mining layout shows: ventilation gate, hydraulic monitors, mine roadway, cross-cut, and collection roadways. A table shows pillar dimensions and depth and economic savings for different seams in the mine.

  11. Stability assessment of the stopes and crown pillar of the S’Argentera abandoned mines (Ibiza, Spain) using geomechanical classifications, an empirical approach and numerical analysis focused on a possible tourist exploitation

    International Nuclear Information System (INIS)

    Jordá-Bordehore, L.; Jordá-Bordehore, R.; Durán Valsero, J.J.; Romero-Crespo, P.L.

    2017-01-01

    The argentiferous lead mines of S’Argentera in Ibiza (Balearic Islands, Spain) are some abandoned underground workings from the first decade of the 20th century. The stability of the main stopes and the crown pillar of the mines has been evaluated - part of which is located below the road between Santa Eulalia and San Carles de Peralta. The possibility of allowing public access to the surface of the mining area and setting up a project of a “show mine” on the underground stopes and galleries is analysed. The stability is assessed with an empirical approach using the O index, the scaled span method and a stability graph together with a numerical approach. Results show that the stopes of the mines are globally stable but some lack an adequate safety factor. Therefore some local reinforcements and monitoring are needed. The finite element modelling in two dimensions yields realistic results on the current stope stability and possible rock falls which have already occurred. [es

  12. Radioactivity of Yatagan lignites and their ash

    International Nuclear Information System (INIS)

    Cicek, F.; Mustafaev, I.; Aliyev, C.

    2004-01-01

    Full text: One of harmful factor of Environmental impact of coal combustion is radiation pollution of Environment. The natural radioisotopes - uranium, thorium and potassium and products of their radioactive destruction contains of radionuclides. These radionuclides in composition of fly ash are thrown to atmosphere from coal combustion furnaces. The concentration of radioisotopes in composition of coals changes in the wide ranges: from 3 up to 520 Becquerel per kilogram (Bq/kg) for Uranium-238 and from 3 up to 320 Bq/kg for thorium-232. The radioactive pollution degree of environment depends on radioisotopes content of initial fuels. In this connection at the estimation of outlook and exploitation of coal mines it is necessary to determine of radioisotopes concentration in coals. That is why investigation of radioisotopes concentration of Turkish lignites has great importance. In this work the radionuclide content of Yatagan lignites and their ash, taken from Gekova thermal Electro station have been studied. The total radiation background generated by these samples was investigated by using of dosimeters 8P-5, CRP-88H, PYB-OIP. Radionuclides content of samples was determined in the Institute of Geology Azerbaijan national Academy of Sciences by using of highly sensitivity gamma-spectrometer CAPU-2, designed by Special Constructor Buro G eophysika . The plant allows to determine the radioisotopes content of solid and liquid samples with highly reliability. It has been established that in sample of lignite uranium content (on the radium equivalent) is 68 Bq/kg, potassium-149 Bq/kg and thorium is absent. The total radioactivity of lignite sample is 79,7 Bq/kg. In the ash sample uranium content is 266 Bq/kg, potassium-188 Bq/kg, and total activity reach to 300 Bq/kg. The possibility of application of purification erection for radionuclides from smoke gases of coal combustion is discussed

  13. Landslides in the area of the Jastrzebie town protective pillar

    Energy Technology Data Exchange (ETDEWEB)

    Rybicki, S

    1986-01-01

    Analyzes 76 landslides in the area of the safety pillar of Jastrzebie in the Rybnik coal region. Of 76 landslides 60% fell on natural slopes with an angle of 25-50 degrees, 22% on natural slopes with a 5-25 degree angle, 10% on man-made cuts and 8% on embankments. About 78% of the landslides was associated with water bearing layers. Of the 76 landslides 32 were situated in the safety pillar and 44 close to the pillar. Thirty-three landslides were closely associated with underground mining: 30 landslides were caused by longwall mining (landslide position was related to working face position), a further 3 were associated with mining in general. Statistical data on landslides associated with underground coal mining are analyzed: landslide area, angle of slope inclination, height, landslide range, water conditions, types of soils, types of mining areas classified according to effects of mining damage. 8 refs.

  14. Natural radioactivity releases from lignite power plants in Southwestern Anatolia

    International Nuclear Information System (INIS)

    Yaprak, G.; Guer, F.; Cam, F.; Candan, O.

    2006-01-01

    The Mugla basin is one of the most productive lignite basins in Southwestern Anatolia, Turkey. Mining activities started in 1979 and total reserves were estimated during exploration at 767.5 million tonnes. Total mean annual lignite production of the Mugla basin is estimated at about 10 million tonnes per year. Most of the lignite production supplies three thermal power plants (Yatagan 630 MW, Yenikoey 420 MW, Kemerkoey 630 MW) with a total capacity of 1680 MW. It is well known that the lignite contains naturally occurring primordial radionuclides arising from the uranium and thorium series as well as from 4 0K. Lignite burning is, therefore, one of the sources of technologically enhanced exposure to humans from natural radionuclides. The investigation reported here deals with the determination of the 2 26Ra, 2 32Th and 4 0K concentrations in the lignite feeding 3 thermal power plants in Mugla region and in the product ash. Samples of lignite feeding the power plants and fly and bottom ashes produced in the same power plants were collected over a period of 1 year and therefore systematic sampling allowed for the determination of mean representative values for the natural radioactivity content of above materials and also estimation of the radioactivity releases to the environment. Furthermore, grid soil sampling within 10-15 km around the power plants allowed for the mapping of the surface soil activity of natural radionuclides. Dosimetric calculations from terrestrial gamma radiation for the population living around the power plants were performed based on the guidance of UNSCEAR 2000 report

  15. Merensky pillar strength formulae based on back-analysis of pillar failures at Impala Platinum

    CSIR Research Space (South Africa)

    Watson, BP

    2008-08-01

    Full Text Available , with and without a large flanking area of mining. Such factors were generally less than 1.2 (20% correction), and were, where feasible, checked using Equation [1]4. This equation may be used if there is a large sea of mining with roughly uniform convergence... for pillars that are allowed to punch, as well as for pillars that are surrounded by an infinitely strong rock mass; high density mesh and varying brittleness Table IV Material and model properties �3 Co �0 �res �pr �0 �res (MPa) (MPa) (m�) A 2 15 55 50...

  16. Recolonization patterns of ants in a rehabilitated lignite mine in central Italy: Potential for the use of Mediterranean ants as indicators of restoration processes

    Energy Technology Data Exchange (ETDEWEB)

    Ottonetti, L.; Tucci, L.; Santini, G. [University of Florence, Florence (Italy)

    2006-03-15

    Ant (Hymenoptera: Formicidae) assemblages were sampled with pitfall traps in three different habitats associated with a rehabilitated mine district and in undisturbed forests in Tuscany, Italy. The four habitats were (1) open fields (3-4 years old); (2) a middle-age mixed plantation (10 years); (3) an old-age mixed plantation (20 years); and (4) an oak woodland (40 years) not directly affected by mining activities. The aim of the study was to analyze ant recolonization patterns in order to provide insights on the use of Mediterranean ant fauna as indicators of restoration processes. Species richness and diversity were not significantly different among the four habitats. However, multivariate analyses showed that the assemblages in the different habitats were clearly differentiated, with similarity relationships reflecting a successional gradient among rehabilitated sites. The observed patterns of functional group changes along the gradient broadly accord with those of previous studies in other biogeographic regions. These were (1) a decrease of dominant Dolichoderinae and opportunists; (2) an increase in the proportion of cold-climate specialists; and (3) the appearance of the Cryptic species in the oldest plantations, with a maximum of abundance in the woodland. In conclusion, the results of our study supported the use of Mediterranean ants as a suitable tool for biomonitoring of restoration processes, and in particular, the functional group approach proved a valuable framework to better interpret local trends in terms of global ecological patterns. Further research is, however, needed in order to obtain a reliable classification of Mediterranean ant functional groups.

  17. Mathematical modelling of transport of gaseous and liquid substances induced by pyrite oxidation in spoil banks of lignite mines; Mathematische Modellierung der durch Pyritoxidation induzierten Stofftransporte in Braunkohleabraumkippen in gasfoermiger und fluessiger Phase

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, R.

    2001-07-01

    Pyrite (FeS{sub 2}) oxidation due to open-pit lignite mining activities may result in acid mine drainage and dissolved metals in the soil and ground water of the overburden spoil piles. The pyrite oxidation takes place firstly during the mining process and at the temporary surfaces of the mine, secondly in deep zones of the overburden spoil pile as a result of gas transport through the unsaturated zone. The second process continues after mine closure possibly over several decades and therefore contaminates the environment for a long time. Whereas some studies deal with a minimisation by geochemical means, this research focuses on a minimisation by impacting the physical boundary conditions. Special attention is given to the transport of oxygen from the soil surface to the pyrite oxidation zone. Soil column experiments with columns of 2.90 m height yield experimental data concerning the pyrite oxidation and the related transport processes in the unsaturated zone. Experimental data are compared to simulation results obtained with the model MUSIC; it calculates coupled reaction and transport processes in a one-dimensional soil profile using the finite volume method. Pyrite oxidation is described by means of a first order kinetics, the gas transport takes place by diffusion as well as convection. The transport of solutes in the soil water is described by the convection-dispersion equation (Cl{sup -}, Fe{sup 2+} and SO{sub 4}{sup 2-}). The simulations are able to reproduce the measured time series of oxygen concentrations in the soil profile. (orig.) [German] Die durch Braunkohlegewinnung im Tagebau hervorgerufene Pyritoxidation (Pyrit: FeS{sub 2}) kann zu Versauerung, Schwermetallfreisetzung und Aufmineralisierung des Boden- und Grundwassers in den Abraumkippen fuehren. Die Pyritoxidation findet zum einen waehrend des Abbaubetriebs und an den temporaeren Oberflaechen des Tagebaus statt, zum anderen in tieferen Bereichen der Abraumkippe durch Gastransport durch die

  18. Influence of geological variations on lignite drying kinetics in superheated steam atmosphere for Belchatow deposit located in the central Poland

    Directory of Open Access Journals (Sweden)

    Sciazko Anna

    2016-01-01

    Full Text Available Lignite-fired coal power plants suffer from a significant heat loss due to the high moisture content in this energy carrier. Water removal from fuel is an indispensable treatment for improving the combustion process, which will foster the efficient utilization of lignite. Superheated steam fluidized bed drying is expected for this purpose in a power generation sector. Understanding drying kinetics of lignite will greatly reinforce design process of a dryer. Physical features as well as the drying behaviour may be divergent among the lignite originated from different depths and positions in a certain mine. To reveal and clarify the influence of the geological features, the drying characteristics of several grades of lignite from the Belchatow mine in Poland were investigated. The attempts to clarify the influence of the divergent properties of the investigated samples on the drying kinetics in superheated steam were presented in this paper.

  19. Mining activities at Neyveli

    International Nuclear Information System (INIS)

    Boopathy, P.V.; Rathinavel, R.

    1993-01-01

    Mining activities at lignite areas around Neyveli are described. Measures taken to safeguard the environment from despoliation of land, air pollution, noise pollution and effluents are described. (M.G.B.)

  20. Capabilities: Science Pillars

    Science.gov (United States)

    Alamos National Laboratory Delivering science and technology to protect our nation and promote world stability Science & Innovation Collaboration Careers Community Environment Science & Innovation Facilities Science Pillars Research Library Science Briefs Science News Science Highlights Lab Organizations

  1. The Mineral Character and Geomechanical Properties of the Transitional Rocks from the Mesozoic-Neogene Contact Zone in the Bełchatów Lignite Deposit

    OpenAIRE

    Agnieszka Pękala

    2014-01-01

    Purpose: Beginning more than 30 years ago, opencast lignite mining in the "Bełchatów" area is an important source of accompanying minerals. Lignite mining in the "Bełchatów" mine yields, on average, more than 35 million tonnes per annum and requires removing more than 110 million cubic meters of overburden. Therefore the mine outside of the main mineral exploitation of lignite, leads to a large-scale economy of accompanying minerals. Part of the minerals are present in the overburden and are ...

  2. The North Dakota lignite partnership

    International Nuclear Information System (INIS)

    Porter, C.R.

    1998-01-01

    The State of North Dakota and the Lignite Energy Council have formed a government/industry partnership to promote the use of North Dakota lignite. The partnership provides funding and management for the Lignite Research, Development and Marketing Program. The program funds activities which preserve and enhance jobs and lignite production; ensure economic growth, stability and opportunity; and maintain a stable and competitive tax base. Funding is provided for activities in three areas: marketing feasibility studies, small research projects, and demonstration projects. Funding is derived from the state coal severance tax. Approximately $3,000,000 annually is appropriated from coal severance revenues for program activities. North Dakota is the ninth largest coal producing state, with lignite as the only rank of coal found in the state. Energy is the second largest economic sector in North Dakota, and it currently comprises over 12% of the state's total economic base. This paper reviews the North Dakota lignite industry and describes studies and projects which have received funding from the program

  3. Development and validation of a method to predict coal pillar life in South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Van Der Merwe, J.N. [Pretoria Univ., Dept. of Mining Engineering (South Africa)

    2005-07-01

    One of the most difficult aspects of mine closure procedures, is to predict the long term stability of pillars in the case of coal mining. In South African coal mining, pillars have been designed since the late 1960's with the aid of a pillar strength formula based on statistical analysis of failed pillar cases by the well known team of Salamon and Munro. They developed the widely used power formula for pillar strength. Since that time, however, the data base of failed pillars has effectively doubled in size and re-analysis of the new data indicated that the original pillar strength of small pillars may have been over estimated. The data was then extensively re-analysed and a more effective linear formula for pillar strength was found. The most important differences between the two formulae are that the predicted strength of small pillars are lower and the strength of larger pillars, higher with the new formula. However, neither of the two methods explicitly cater for the prediction of the expected time of stability of coal pillars. No direct correlation between the safety factors and the period of stability of pillars could be found. It was then determined that the most frequent mode of pillar failure was by progressive scaling. Using the new formula to determine a minimum value of pillar safety factor (i.e. the safety factor at which failure can be taken as guaranteed to occur), the final sizes - after scaling - at which the failed pillars had to be in order to fail, were determined. The differences between the original dimensions and the postulated final dimensions were then used to calculate a rate of pillar scaling. The rate was then re-applied to the original data bases of both failed and intact pillar cases and distinct differences were found. The projected lives of the failed pillars were substantially shorter than the projected lives of the intact pillars. While this inspired confidence in the procedure, it was still based on an assumed and unproven

  4. Development and validation of a method to predict coal pillar life in South Africa

    International Nuclear Information System (INIS)

    Van Der Merwe, J.N.

    2005-01-01

    One of the most difficult aspects of mine closure procedures, is to predict the long term stability of pillars in the case of coal mining. In South African coal mining, pillars have been designed since the late 1960's with the aid of a pillar strength formula based on statistical analysis of failed pillar cases by the well known team of Salamon and Munro. They developed the widely used power formula for pillar strength. Since that time, however, the data base of failed pillars has effectively doubled in size and re-analysis of the new data indicated that the original pillar strength of small pillars may have been over estimated. The data was then extensively re-analysed and a more effective linear formula for pillar strength was found. The most important differences between the two formulae are that the predicted strength of small pillars are lower and the strength of larger pillars, higher with the new formula. However, neither of the two methods explicitly cater for the prediction of the expected time of stability of coal pillars. No direct correlation between the safety factors and the period of stability of pillars could be found. It was then determined that the most frequent mode of pillar failure was by progressive scaling. Using the new formula to determine a minimum value of pillar safety factor (i.e. the safety factor at which failure can be taken as guaranteed to occur), the final sizes - after scaling - at which the failed pillars had to be in order to fail, were determined. The differences between the original dimensions and the postulated final dimensions were then used to calculate a rate of pillar scaling. The rate was then re-applied to the original data bases of both failed and intact pillar cases and distinct differences were found. The projected lives of the failed pillars were substantially shorter than the projected lives of the intact pillars. While this inspired confidence in the procedure, it was still based on an assumed and unproven rate

  5. Evolution of Early Pleistocene fluvial systems in central Poland prior to the first ice sheet advance – a case study from the Bełchatów lignite mine

    Directory of Open Access Journals (Sweden)

    Goździk Jan

    2017-06-01

    Full Text Available Deposits formed between the Neogene/Pleistocene transition and into the Early Pleistocene have been studied, mainly on the basis of drillings and at rare, small outcrops in the lowland part of Polish territory. At the Bełchatów lignite mine (Kleszczów Graben, central Poland, one of the largest opencast pits in Europe, strata of this age have long been exposed in extensive outcrops. The present paper is based on our field studies and laboratory analyses, as well as on research data presented by other authors. For that reason, it can be seen as an overview of current knowledge of lowermost Pleistocene deposits at Bełchatów, where exploitation of the Quaternary overburden has just been completed. The results of cartographic work, sedimentological, mineralogical and palynological analyses as well as assessment of sand grain morphology have been considered. All of these studies have allowed the distinction of three Lower Pleistocene series, i.e., the Łękińsko, Faustynów and Krzaki series. These were laid down in fluvial environments between the end of the Pliocene up to the advance of the first Scandinavian ice sheet on central Poland. The following environmental features have been interpreted: phases of river incision and aggradation, changes of river channel patterns, source sediments for alluvia, rates of aeolian supply to rivers and roles of fluvial systems in morphological and geological development of the area. The two older series studied, i.e., Łękińsko and Faustynów, share common characteristics. They were formed by sinuous rivers in boreal forest and open forest environments. The Neogene substratum was the source of the alluvium. The younger series (Krzaki formed mainly in a braided river setting, under conditions of progressive climatic cooling. Over time, a gradual increase of aeolian supply to the fluvial system can be noted; initially, silt and sand were laid down, followed by sand only during cold desert conditions. These

  6. THERMODYNAMIC ANALYSIS OF CARBON SEQUESTRATION METHODS IN LIGNITE POWER PLANTS

    International Nuclear Information System (INIS)

    Koroneos J. Christopher; Sakiltzis Christos; Rovas C. Dimitrios

    2008-01-01

    The green house effect is a very pressing issue of our times due to the big impact it will have in the future of life in our planet. The temperature increase of the earth which is the major impact of the greenhouse effect may change forever the climate and the way of life in many countries. It may lead to the reduction of agricultural production and at the end to famine, in several nations. The minimization of CO2 emissions and the introduction of new energy sources is the only solution to the catastrophe that is coming if inaction prevails. The objective of this work is to analyze the methods of the CO2 removal from the flue gases of power plants that use solid fuels. It is especially fit to the Greek conditions where the main fuel used is lignite. Three methods have been examined and compared thermodynamically. These are: (a) Removal of CO2 from the flue gas stream by absorption, (b) The combustion of lignite with pure oxygen and (c) The gasification of lignite. The lignite used in the analysis is the Greek lignite, produced at the Western Macedonia mines. The power plant, before carbon sequestration, has an efficiency of 39%, producing 330MW of electric power. After sequestration, the CO2 is compressed to pressures between 80-110 atm, before its final disposal. In the first method, the sequestration of CO2 is done utilizing a catalyst. The operation requires electricity and high thermal load which is received from low pressure steam extracted from the turbines. Additionally, electricity is required for the compression of the CO2 to 100 bars. This leads to a lower efficiency of the power plant by by 13%. In the second method, the lignite combustion is done with pure O2 produced at an air separation unit. The flue gasses are made up of CO2 and water vapor. This method requires electricity for carbon dioxide compression and the Air Separation unit, thus, the power plant efficiency is lowered by 26%. In the lignite gasification method, the products are a mixture of

  7. Evaluation of lignite tar

    Energy Technology Data Exchange (ETDEWEB)

    Gossedin, A

    1946-01-01

    Tar from the low-temperature (450/sup 0/) carbonization of lignite from Bouches-du-Rhone was hydrogenated in the presence of a catalyst based on MoS/sub 2/ with a 3:1 H:N mixture. Processing (at 470/sup 0/ and 400 atmospheres) for maximum production of gasoline yielded 86 wt % of a product of boiling 55 to 186/sup 0/ and motor octane number 75. An alternative is to hydrogenate with a view to producing solvents and lubricants. For this purpose the tar was separated by distillation (at 20 millimeters, cutting at 220/sup 0/) into two fractions of equal volume. On hydrogenation (at 300/sup 0/ and 400 atmospheres) the light part yields a gasoline H/sub 2/O-soluble cut, a highly aromatic solvent fraction, a heavier cut (280/sup 0/ to 320/sup 0/) suitable as a plasticizer, and a phenol fraction. The heavier part of the tar is hydrogenated (at 380/sup 0/ and 400 atmospheres) to give spindle oil and lubricating oil of medium eta (11.2 centistokes at 98.2/sup 0/), moderate eta index (64), good pour point (-7/sup 0/), and good oxidizing characteristics. The overall yield of products from the two portions is 86.9% (gasoline and solvent 32, light phenols 9.7, spindle oil 14.2, medium lubricating oil 25.7, wax, 5.3%).

  8. Development potential of former lignite mining areas and future need for action considering environmental protection - a review of research and remediation results in former east-German lignite mining areas; Entwicklungspotenziale der Bergbaufolgelandschaft und zukuenftiger Handlungsbedarf aus der Sicht des Naturschutzes - Ein Ueberblick zu den Ergebnissen der Forschung und Sanierung in den ehemaligen ostdeutschen Braunkohleregionen

    Energy Technology Data Exchange (ETDEWEB)

    Tischew, S. [Hochschule Anhalt (F.H.), Bernburg (Germany). Fachbereich 1

    2004-07-01

    Based on the knowledge of nature conservation value of surface-mined land in Eastern Germany a review of research activities since 1993 was made. The focal point was the integration of nature conservation goals into the sustainable development of former mining sites. Reference states were developed that were based on natural processes and biodiversity. To include the results in restoration scheme abiotic and biotic factors essential for the development of valuable biotopes and their characteristic animal and plant communities were analysed. Algorithms for the prognosis of successional processes were developed including the main development factors: succession and the rise of the groundwater table. The research results show a high natural regeneration potential of most post-mining areas. Spontaneous succession leads to diverse landscape structures with a high biodiversity at several hierarchical levels (species, biocoenosises and biotopes). These successional stages are more appreciated by public than afforested or managed sites. They emphasize the characteristic features of post-mining landscapes and represent as well a potential for tourism ('wilderness'). Anyway, natural development seems to be a cost-efficient alternative to expensive reclamation methods. In the future, these positive links should be taken more into account. The research projects developed concepts for integrating scientific results in practise: (1) criteria for selection of priority areas for nature conservation, (2) proposals for creation and development of these areas and (3) methods for the acceleration of vegetation development on sensible slopes and shore lines based on natural successional series. About 20% of the post-mining landscape was integrated in a network of nature conservation areas and habitat connectivity. Future research is necessary because of the current rise of the groundwater and the ongoing successional processes. On account of the complex mechanism of action

  9. Economics of mine water treatment

    OpenAIRE

    Dvořáček, Jaroslav; Vidlář, Jiří; Štěrba, Jiří; Heviánková, Silvie; Vaněk, Michal; Barták, Pavel

    2012-01-01

    Mine water poses a significant problem in lignite coal mining. The drainage of mine water is the fundamental prerequisite of mining operations. Under the legislation of the Czech Republic, mine water that discharges into surface watercourse is subject to the permission of the state administration body in the water management sector. The permission also stipulates the limits for mine water pollution. Therefore, mine water has to be purified prior to discharge. Although all...

  10. Recovery of uranium from lignites

    International Nuclear Information System (INIS)

    Hurst, F.J.

    1980-01-01

    Uranium in raw lignite is associated with the organic matter and is readily soluble in acid (and carbonate) solutions. However, beneficiation techniques were not successful for concentrating the uranium or removing part of the reagent-consuming materials. Once the lignite was heated, the uranium became much less soluble in both acid and carbonate solutions, and complete removal of carbon was required to convert it back to a soluble form. Proper burning improves acid-leaching efficiency; that is, it reduces the reagent consumption and concentrates the uranium, thereby reducing plant size for comparable uranium throughput, and it eliminates organic fouling of leach liquors. Restrictions are necessary during burning to prevent the uranium from becoming refractory. The most encouraging results were obtained by flash-burning lignite at 1200 to 1300 0 C and utilizing the released SO 2 to supplement the acid requirement. The major acid consumers were aluminum and iron

  11. Texas turns on lignite

    International Nuclear Information System (INIS)

    Faulkner, T.

    1992-01-01

    The paper describes the author's involvement with the Texas Mining and Reclamation Association (TMRA) and some of its activities. The mission of TMRA is to solidify the needs and opinions of the various mining sectors into one voice which can be heard on the vital matters of balance between mineral production, environmental protection, economic strength and public welfare. To make this voice effective, TMRA will present the mining industry - and its value to the Texas economy and lifestyle - to the public, educators and students, regulatory officials, legislators and to the media to enhance their understanding. TMRA will promote the active participation of its members in association affairs and strive for integrity, clarity and vision throughout all its operations and activities

  12. Develop international links for cooperative research in coal mining with special emphasis on interaction with international experts for developing industry guidelines for the design of pillars in coal mines

    CSIR Research Space (South Africa)

    Van der Merwe, JN

    2001-07-01

    Full Text Available of these was held in Johannesburg in 2000, in conjunction with the International Conference on Coal Research (ICCR). At that meeting, it was resolved to attempt to have more meetings of a similar nature. The first was to be in Australia in 2001..., there is always a danger that what is written could be used out of context. Readers are requested to refrain from this practice. 2 Background To The Workshop During the period 1977 to 1992 15 pillar collapse cases occurred in Australia. Six of these were...

  13. Fractal morphology in lignite coal: a small angle x-ray scattering investigation

    International Nuclear Information System (INIS)

    Chitra, R.; Sen, D.; Mazumder, S.; Chandrasekaran, K.S.

    1999-01-01

    Small angle x-ray scattering technique has been used to study the pore morphology in lignite coal from Neyveli lignite mine (Tamilnadu, India). The sample were collected from three different locations of the same mine. SAXS profiles from all the three samples show almost identical functionality, irrespective of the locations from where the samples were collected. SAXS experiment using two different wavelengths also exhibit same functionality indicating the absence of multiple scattering. The analysis indicates the surface fractal nature of the pore morphology. The surface fractal dimension is calculated to be 2.58. (author)

  14. Swedish mines. Underground exploitation methods

    International Nuclear Information System (INIS)

    Paucard, A.

    1960-01-01

    Between 1949 and 1957, 10 engineers of the Mining research and exploitation department of the CEA visited 17 Swedish mines during 5 field trips. This paper presents a compilation of the information gathered during these field trips concerning the different underground mining techniques used in Swedish iron mines: mining with backfilling (Central Sweden and Boliden mines); mining without backfilling (mines of the polar circle area). The following techniques are described successively: pillar drawing and backfilled slices (Ammeberg, Falun, Garpenberg, Boliden group), sub-level pillar drawing (Grangesberg, Bloettberget, Haeksberg), empty room and sub-level pillar drawing (Bodas, Haksberg, Stripa, Bastkarn), storage chamber pillar drawing (Bodas, Haeksberg, Bastkarn), and pillar drawing by block caving (ldkerberget). Reprint of a paper published in Revue de l'Industrie Minerale, vol. 41, no. 12, 1959 [fr

  15. Effect of structural discontinuities on coal pillar strength as a basis for improving safety in the design of coal pillar systems.

    CSIR Research Space (South Africa)

    Esterhuizen, GS

    1998-12-01

    Full Text Available The stability of underground coal mines depends on the integrity of the pillars which are required to support the overlying strata. Should the pillars collapse, the safety of the persons in the workings will be threatened. The strength of a coal...

  16. Power generation from lignite coal in Bulgaria - problems and solutions

    International Nuclear Information System (INIS)

    Batov, S.; Gadjanov, P.; Panchev, T.

    1997-01-01

    The bulk of lignite coal produced in Bulgaria is used as fuel for the thermal power plants (TPP) built in Maritsa East coal field. A small part of it goes to production of briquettes and to fuel the auxiliary power plants of industrial enterprises. The total installed capacity of the power plants in the region of Maritsa East is 2490 MW, and the electric power generated by them is about 30% of the total power generated in the country. It should be noted that these power plants were subjected to a number of rehabilitations aiming to improve their technical and economic parameters. Irrespective of that, however, solution has still to be sought to a number of problems related to utilisation of the low-grade lignite coal for power generation. On the whole, they can be divided in the following groups: Those related to lignite coal mining can be referred to the first group. Lignite coal is mined in comparatively complicated mining and geological conditions characterized mainly by earth creep and deformation. The second group of problems is related to coal quality control. It is a fact of major significance that the quality indices of coal keep changing all the time in uneven steps without any definite laws to govern it. That creates hard problems in the process of coal transportation, crushing and combustion. The next group of problems concerns operation and upgrading of the power generation equipment. That applies especially to the existing boilers which bum low-grade fuel in order to improve their operation in terms of higher thermal efficiency, controllability, reliability, improved environmental indices, etc. An increasingly high importance is attached to environmental impact problems incident to lignite coal utilisation. Abatement of sulphur oxide emissions and dust pollution is a problem solution of which cannot wait. The possibilities for partial solution of the environmental problems through increasing the thermal efficiency of facilities at the thermal Power

  17. Macedonian lignite - upgrading and evaluation

    International Nuclear Information System (INIS)

    Musich, Mark A.; Young, Brian C.

    1997-01-01

    Macedonian lignites have a high moisture content, low heating value, and are friable, generating fines and dust. Macedonia has an urgent need to use indigenous solid fuel resources for domestic and industrial heating as well as metallurgical applications. The goal of this project was to evaluate the potential for beneficiating Macedonian lignite and producing high-quality briquettes for metallurgical use as well as domestic/industrial heating. Laboratory studies have shown that treating the Macedonian lignite fines by two physical processes-cleaning and carbonization-followed by pelletizing. can generate acceptable lump fuels for heating applications. Carbonizing the float-sink-cleaned lignite to reduce the volatile matter content and pelletizing the resultant char with starch produced strong pellets, which could be used as a home-heating fuel, the char having a heat content of 13,400 Btu/lb (31.2 MJ/Kg). However, additional work is required at the pilot scale to determine optimum briquetting conditions and production costs. (Author)

  18. The possibility of increasing the efficiency of accessible coal deposits by optimizing dimensions of protective pillars or the scope of exploitation

    Science.gov (United States)

    Bańka, Piotr; Badura, Henryk; Wesołowski, Marek

    2017-11-01

    One of the ways to protect objects exposed to the influences of mining exploitation is establishing protective pillars for them. Properly determined pillar provides effective protection of the object for which it was established. Determining correct dimensions of a pillar requires taking into account contradictory requirements. Protection measures against the excessive influences of mining exploitation require designing the largest possible pillars, whereas economic requirements suggest a maximum reduction of the size of resources left in the pillar. This paper presents algorithms and programs developed for determining optimal dimensions of protective pillars for surface objects and shafts. The issue of designing a protective pillar was treated as a nonlinear programming task. The objective function are the resources left in a pillar while nonlinear limitations are the deformation values evoked by the mining exploitation. Resources in the pillar may be weighted e.g. by calorific value or by the inverse of output costs. The possibility of designing pillars of any polygon shape was taken into account. Because of the applied exploitation technologies the rectangular pillar shape should be considered more advantageous than the oval one, though it does not ensure the minimization of resources left in a pillar. In this article there is also presented a different approach to the design of protective pillars, which instead of fixing the pillar boundaries in subsequent seams, the length of longwall panels of the designed mining exploitation is limited in a way that ensures the effective protection of an object while maximizing the extraction ratio of the deposit.

  19. 30 CFR 75.203 - Mining methods.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Mining methods. 75.203 Section 75.203 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Roof Support § 75.203 Mining methods. (a) The method of mining... faulty pillar recovery methods. Pillar dimensions shall be compatible with effective control of the roof...

  20. Treatment of lignite tars, etc

    Energy Technology Data Exchange (ETDEWEB)

    1936-08-07

    A process is described for treating tars such as lignite tar, shale tar, or peat tar, and similar tars, characterized by the fact that the tar is rectified to about 240/sup 0/C and the residue brought to a temperature above 50/sup 0/C after diluting with a product of the type of gasoline or ligroin at about 30/sup 0/C and treated with selective solvents preferably low-boiling phenols and eventually with water.

  1. The German lignite industry. Historical development, resources, technology, economic structures and environmental impact. Study

    International Nuclear Information System (INIS)

    2017-05-01

    Lignite has a key role to play in the transformation of the energy system due to its specific structural features in terms of industry, company history, policy, economics, the environment and regional structures. Understanding these structural features of the German lignite industry is an important requirement for classifying the significance of the lignite industry up to now and for the redesigning of this industrial sector. From these environmental, economic and regulatory structural characteristics, which are interwoven in a variety of ways, the incentives arise for the mining and power plant operators to react to energy price signals or energy policy steering. The aim of this research study is to define these structural features, to compile comprehensively the basic data and information that is not always transparently available, to understand the interactions, to enable the navigation of issues that are partly very complex, and to classify into the long-term developments that are especially important for political and social processes. In 2016 approx. 12 percent of German primary energy consumption was met using lignite. At the same time, lignite has the highest carbon dioxide (CO2) emissions of the fossil fuels; it currently accounts for approx. 19 percent of Germany's total greenhouse gas emissions as well as approx. 46 percent of the total CO2 emissions of the electricity sector. As a result of the mining of lignite and its conversion into electricity, substantial adverse impacts beyond the entry of greenhouse gases into the Earth's atmosphere arise for other environmental media. These impacts include half of Germany's mercury emissions, approx. a third of its sulfur dioxide emissions and approx. a tenth of its nitrogen oxide emissions. Lignite mining in open-cast mines takes up a substantial amount of landscape and soil and requires huge interventions in the water balance. Relatively high costs arise for the recultivation and rehabilitation of the open

  2. THE COMBUSTION CHARACTERISTICS OF LIGNITE BLENDS

    Institute of Scientific and Technical Information of China (English)

    Cheng Jun; Zhou Junhu; Cao Xinyu; Cen Kefa

    2000-01-01

    The combustion characteristics of lignite blends were studied with a thermogravimetric analyzer (t.g.a.), at constant heating rate.The characteristic temperatures were determined from the burning profiles.It was found that the characteristic times of combustion reaction moved forward, the ignition temperature dropped and the burnout efficiency slightly changed when blending lignites.The characteristic parameters of blends could not be predicted as a linear function of the average values of the individual lignites.when blending with less reactive coal, the ignition and burnout characteristics of lignite turned worse.

  3. Influence of chemical structure on carbon isotope composition of lignite

    Science.gov (United States)

    Erdenetsogt, Bat-Orshikh; Lee, Insung; Ko, Yoon-Joo; Mungunchimeg, Batsaikhan

    2017-04-01

    During the last two decades, a number of studies on carbon isotopes in terrestrial organic matter (OM) have been carried out and used to determine changes in paleoatmospheric δ13C value as well as assisting in paleoclimate analysis. Coal is abundant terrestrial OM. However, application of its δ13C value is very limited, because the understanding of changes in isotopic composition during coalification is relatively insufficient. The purpose of this study was to examine the influence of the chemical structure on the carbon isotope composition of lignite. Generally, lignite has more complex chemical structures than other higher rank coal because of the existence of various types of oxygen-containing functional groups that are eliminated at higher rank level. A total of sixteen Lower Cretaceous lignite samples from Baganuur mine (Mongolia) were studied by ultimate, stable carbon isotope and solid-state 13C CP/MAS NMR analyses. The carbon contents of the samples increase with increase in depth, whereas oxygen content decreases continuously. This is undoubtedly due to normal coalification process and also consistent with solid state NMR results. The δ13C values of the samples range from -23.54‰ to -21.34‰ and are enriched in 13C towards the lowermost samples. Based on the deconvolution of the NMR spectra, the ratios between carbons bonded to oxygen (60-90 ppm and 135-220 ppm) over carbons bonded to carbon and hydrogen (0-50 ppm and 90-135 ppm) were calculated for the samples. These correlate well with δ13C values (R2 0.88). The results indicate that the δ13C values of lignite are controlled by two mechanisms: (i) depletion in 13C as a result of loss of isotopically heavy oxygen-bounded carbons and (ii) enrichment in 13C caused by a loss of isotopically light methane from aliphatic and aromatic carbons. At the rank of lignite, coal is enriched in 13C because the amount of isotopically heavy CO2 and CO, released from coal as a result of changes in the chemical

  4. Radiation doses of inhaled ash from the lignite power plants

    International Nuclear Information System (INIS)

    Boshevski, Tome; Pop-Jordanov, Jordan; Chaushevski, Anton

    1997-01-01

    The coal-fired thermal power plants in Macedonia use lignite obtained by surface mining. The lignite contains traces of thorium-232, uranium-238 and uranium-235, which are long-lived natural radioactive isotopes. After lignite combustion, the concentration of these isotopes in the ash is increased. Due to the long life of fossil materials, the decay products are basically grouped in three radioactive chains that are in a semi-steady state, resulting in equal activity of all isotopes from the chain. Among the members of each chain there are α and β emitters followed by γ quanta emitters. The energies of the α and β particles are important for determining the effective dose. The γ quanta provide information about the chain activity and isotope types. Gamma-spectroscopy studies of the ash samples from the power plants in the City of Bitola in Macedonia have confirmed the presence of several radioactive decay products from the uranium and thorium radioactive chains. Using measurements of the radioactivity of the ash in the Bitola region, the total dose from ash inhalation for the population in the Bitola region was calculated and presented in this paper. Also, analysis of the procedure for determining the maximum allowable dose from radioactive contamination of the environment, is described in this paper. (Original)

  5. Lusatian lignite. Decisions for the future; Lausitzer Braunkohle. Entscheidungen fuer die Zukunft

    Energy Technology Data Exchange (ETDEWEB)

    Daehnert, Detlev [Vattenfall Europe Mining AG, Cottbus (Germany); Vattenfall Europe Generation AG und Co. KG, Cottbus (Germany); Ketzmer, Wolfgang [Vattenfall Europe Generation AG und Co. KG, Cottbus (Germany)

    2008-07-15

    During the past months a number of important decisions regarding the future of the Lusatian lignite mining areas have been made or launched. In the focus is the concept of the long-term opencast mine and power plant development. Essential part of the concept is the strategy for meeting future challenges of climate change policy. CCS is the key for it. It is expected, that the CCS technology will be commercially available after 2020. Another important aspect is among others the use of the priority areas of the Welzow-Sued and Nochten opencast mined. The corresponding long-term lignite mining planning procedures were opened in autumn 2007. The plans of the company contain clear and reliable statements regarding the long-term opencast mine development until 2050. However, all decisions the company makes are focussing on putting people and their needs first. Solutions for mining related questions and requirements are jointly developed with the people of the region. Communities in direct neighbourhood to opencast mines are safely protected against immissions by structural and organisational measures. The principles of socially responsible resettlements set the framework of constructive and trustful co-acting of the people concerned and the company very early. The future post-mining landscape offers alternative utilization forms providing employment for many people. Economic development of the region is an important aspect of the company's activities. Under the headline ''Energy region Lusatia'', representatives of Vattenfall, different educational institutions, authorities and the politics have joined forces to formulate a strategic target for the future development of Lusatia. Sustainable development of lignite-based power generation to meet future climate change policy, development of energy industrial know-how and the use of other fuels are important issues. The results are visible. Lignite takes a solid place in the German Energy mix - it

  6. Pillar-type acoustic metasurface

    DEFF Research Database (Denmark)

    Jin, Yabin; Bonello, Bernard; Moiseyenko, Rayisa

    2017-01-01

    We theoretically investigate acoustic metasurfaces consisting of either a single pillar or a line of identical pillars on a thin plate, and we report on the dependence on the geometrical parameters of both the monopolar compressional and dipolar bending modes. We show that for specific dimensions...

  7. Development of a method to estimate coal pillar loading

    CSIR Research Space (South Africa)

    Roberts, DP

    2002-09-01

    Full Text Available to the panel width to depth ratio, the percentage extraction and the stiffness of the surrounding strata influence the validity of the tributary area method. An underground test was conducted to assess the magnitude of changes in pillar stress. Various... stress measurement devices were installed in test pillars just prior to mining. The stress changes were monitored and compared with numerical modelling results. It was found that stresses increased by between 0.3 MPa and 0.5 MPa and that the stresses...

  8. Three Philosophical Pillars That Support Collaborative Learning.

    Science.gov (United States)

    Maltese, Ralph

    1991-01-01

    Discusses three philosophical pillars that support collaborative learning: "spaces of appearance," active engagement, and ownership. Describes classroom experiences with collaborative learning supported by these pillars. (PRA)

  9. COFIRING BIOMASS WITH LIGNITE COAL

    Energy Technology Data Exchange (ETDEWEB)

    Darren D. Schmidt

    2002-01-01

    The University of North Dakota Energy & Environmental Research Center, in support of the U.S. Department of Energy's (DOE) biomass cofiring program, completed a Phase 1 feasibility study investigating aspects of cofiring lignite coal with biomass relative to utility-scale systems, specifically focusing on a small stoker system located at the North Dakota State Penitentiary (NDSP) in Bismarck, North Dakota. A complete biomass resource assessment was completed, the stoker was redesigned to accept biomass, fuel characterization and fireside modeling tests were performed, and an engineering economic analysis was completed. In general, municipal wood residue was found to be the most viable fuel choice, and the modeling showed that fireside problems would be minimal. Experimental ash deposits from firing 50% biomass were found to be weaker and more friable compared to baseline lignite coal. Experimental sulfur and NO{sub x} emissions were reduced by up to 46%. The direct costs savings to NDSP, from cogeneration and fuel saving, results in a 15- to 20-year payback on a $1,680,000 investment, while the total benefits to the greater community would include reduced landfill burden, alleviation of fees for disposal by local businesses, and additional jobs created both for the stoker system as well as from the savings spread throughout the community.

  10. French pollution and German lignite

    International Nuclear Information System (INIS)

    Foos, Jacques

    2015-01-01

    After having recalled that the German energy transition is based on a complete shutting down of nuclear power stations to replace them by renewable energy sources on the one hand, and by coal (lignite, i.e. the dirtiest coal) and gas on the other hand to compensate the intermittency of the former ones, this article notices that pollution peaks occurred in France when an eastern of north-eastern wind was blowing, and not in case of western wind. The author then wanders whether this pollution comes from Germany, and more particularly from the releases of lignite-fuelled power stations. Then, the author comments the high level of pollution associated with coal extraction and exploitation in Germany, causing thousands of deaths and resulting in lung diseases or cancers, myocardial infractions. The author then makes a parallel between, on the one hand, the ignorance of this German pollution and, on the other hand, evacuation measures around Fukushima for a radioactivity which the author considers as less dangerous in terms of life expectancy

  11. Bioprocessing of lignite coals using reductive microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, D.L.

    1992-03-29

    In order to convert lignite coals into liquid fuels, gases or chemical feedstock, the macromolecular structure of the coal must be broken down into low molecular weight fractions prior to further modification. Our research focused on this aspect of coal bioprocessing. We isolated, characterized and studied the lignite coal-depolymerizing organisms Streptomyces viridosporus T7A, Pseudomonas sp. DLC-62, unidentified bacterial strain DLC-BB2 and Gram-positive Bacillus megaterium strain DLC-21. In this research we showed that these bacteria are able to solubilize and depolymerize lignite coals using a combination of biological mechanisms including the excretion of coal solublizing basic chemical metabolites and extracellular coal depolymerizing enzymes.

  12. Stress reduction for pillar filled structures

    Science.gov (United States)

    Nikolic, Rebecca J.; Conway, Adam; Shao, Qinghui; Voss, Lars; Cheung, Chin Li; Dar, Mushtaq A.

    2015-09-01

    According to one embodiment, an apparatus for detecting neutrons includes an array of pillars, wherein each of the pillars comprises a rounded cross sectional shape where the cross section is taken perpendicular to a longitudinal axis of the respective pillar, a cavity region between each of the pillars, and a neutron sensitive material located in each cavity region.

  13. Production of rubbly culm coke from lignite

    Energy Technology Data Exchange (ETDEWEB)

    Koenigs, H B [Rheinische Braunkohlenwerke A.G., Koeln (Germany, F.R.). Hauptabteilung Kohleverarbeitung; Kurtz, R [Rheinische Braunkohlenwerke A.G., Frechen (Germany, F.R.). Abt. Verkokung und Chemie

    1977-08-01

    The article deals with the coke supply of the iron and steel industry, the design, function, and special features of the open-hearth, and describes the coking properties and applications of the culm coke produced from lignite.

  14. Ash content of lignites - radiometric analysis

    International Nuclear Information System (INIS)

    Leonhardt, J.; Thuemmel, H.W.

    1986-01-01

    The quality of lignites is governed by the ash content varying in dependence upon the geologic conditions. Setup and function of the radiometric devices being used for ash content analysis in the GDR are briefly described

  15. Germany's lignite industry in 2011; Die deutsche Braunkohlenindustrie im Jahr 2011

    Energy Technology Data Exchange (ETDEWEB)

    Maassen, Uwe [Bundesverband Braunkohle, Koeln (Germany); Statistik der Kohlenwirtschaft e.V., Koeln (Germany); Schiffer, Hans-Wilhelm [RWE Aktiengesellschaft, Essen (Germany)

    2012-05-15

    From 2010 to 2011, Germany's domestic lignite output edged up 4.2% from 169.4 mill. t to 176.5 mill. t. This output is equivalent to a net calorific value of 54.4 mill. tce; of the total output, 157.4 mill. t, or some 90% was used in utility power plants for public supply. That was 3.6% more than in the previous year; 15.5 mill. t was input in the factories of the lignite-mining industry to make solid products, while 2.6 mill. t was used to generate electricity in mine-mouth power plants. Other sales of raw lignite and changes in stocks accounted for 1.0 mill. t. Lignite made a 24.9% contribution toward Germany's total power generation in 2011. In 2011, lignite had an 11.7% share in primary-energy consumption, giving it slot four in Germany's energy-consumption balance after mineral oil (34.0%), natural gas (20.4%) and hard coal (12.6%). Renewable resources cover 10.9, while nuclear energy accounts for 8.8% and other energy sources for 1.6%. With output of 54.4 mill. tce, lignite held a share of 38,5% in Germany's primary-energy production of some 141.3 mill. tce. The contributions made by the other energy carriers to primary-energy production in 2011 were as follows: 12.3 mill. tce hard coal, 13.1 mill. tce gas, 3.9 mill tce mineral oil, 49.5 mill. tce renewables, and 8.1 mill. tce other energy sources. Of the total electricity that Germany produced in 2011, 24,9% was accounted for by lignite. This means that lignite led the ranking of the most important input energies for electricity generation in 2011, followed by renewables with 19.9% hard coal with 18.6%, nuclear energy with 17.6% and gas with 13.7%. Other energy sources made a 5.3% contribution to total gross power generation. The most important ratios for the contributions made by the various lignite-mining areas to Germany's energy supply was shown. CO{sub 2} emissions from lignite rose 3.7% from 168.7 mill. t in 2010 to 175 mill. t in 2011. In the entire period from 1990 to 2011, a

  16. Germany's lignite industry in 2012; Die deutsche Braunkohlenindustrie im Jahr 2012

    Energy Technology Data Exchange (ETDEWEB)

    Maassen, Uwe [Bundesverband Braunkohle, Statistik der Kohlenwirtschaft e.V., Koeln (Germany); Schiffer, Hans-Wilhelm [RWE Aktiengesellschaft, Essen (Germany). CEA-W Allgemeine Wirtschaftspolitik/Wissenschaft

    2013-05-15

    From 2011 to 2012, Germany's domestic lignite output edged up to 5.1% from 176.5 mill. t to 185.4 mill. t. This figure is equivalent to a net calorific value of 57.2 mill. tce. Of the total output, 166.3 mill. t, or some 90%, was used in utility power plants for the public supply, i.e. 5.7% more than in the previous year. In addition, 15.1 mill. t was input in the factories of the lignite-mining industry to make solid products, while 3.0 mill. t was used to generate electricity in mine-mouth power plants. Other sales of raw lignite and changes in stocks accounted for 1.0 mill. t. Lignite made a 25.7% contribution toward Germany's total power generation in 2012. In 2012, lignite had a 12.1% share in primary-energy consumption balance after mineral oil (33.1%), natural gas (21.6%) and hard coal (12.2%). Renewable resources cover 11.6%, while nuclear energy accounts for 8.0% and other energy sources for 1.4%. With output of 57.2 mill. tce, lignite held a share of 38.4% in Germany's primary-energy production of some 149 mill. tce in 2012. The contributions made by other energy carriers to primary-energy production in 2012 were as follows: 11.1 mill. tce hard coal, 13.3 mill. tce gas, 3.8 mill. tce mineral oil, 54.0 mill. tce renewables, and 9.5 mill. tce other energy sources. Of the total electricity amount that Germany produced in 2012, 25.7% was accounted for by lignite. This means that lignite led the ranking of the most important input energies for electricity generation in 2012, followed by renewables with 22.1%, hard coal with 19.1%, nuclear energy with 16.1% and gas with 11.3%. Other energy sources made a 5.7% contribution to total gross power generation. The most important ratios for the contributions made by the various lignite-mining areas to Germany's energy supply are shown. CO{sub 2} emissions from lignite rose 5.1% from 173.9 mill. t in 2011 to 182.8 mill. t in 2012. In the total period from 1990 to 2012, a decline of 159.4 mill. t, or

  17. The use of virtual reality to simulate room and pillar operations

    Energy Technology Data Exchange (ETDEWEB)

    Crawshaw, S A.M.; Denby, B; McClarnon, D [Long-Airdox International Limited, Ilkeston (United Kingdom)

    1997-01-01

    Virtual Reality systems allow a user to interact with dynamic three-dimensional computer models of real world situations. The authors show how the complexity of room and pillar mining operations may be mirrored in a user-configurable system. Additionally, an understanding is gained of the mining method, and the operation of equipment in the actual working environment. 1 ref., 5 figs.

  18. Coal mining situation in the Federal Republic of Germany. The 1st quarter 2015

    International Nuclear Information System (INIS)

    2015-01-01

    The paper reports on the coal mining in the Federal Republic of Germany in the 1st quarter of 2015. Statistical data are presented for mining, exports and imports of hard coal and lignite and for employees.

  19. Coal mining situation in the Federal Republic of Germany. The 1st quarter 2017

    International Nuclear Information System (INIS)

    2017-01-01

    The paper reports on the coal mining in the Federal Republic of Germany in the 1st quarter of 2017. Statistical data are presented for mining, exports and imports of hard coal and lignite and for employees.

  20. Possibilities of utilizing the Hungarian reserves of lignite in thermal power stations

    Energy Technology Data Exchange (ETDEWEB)

    Faur, G

    1978-01-01

    The Upper Pannonian lignite reserves subjected to study are suited to opencast mining with respect to their depth and thickness. All of them are characterized by occurrence in multiple beds, the thickness of which however is different per area. The dirt between the strata consists mostly of sand, to a lesser degree of clay or of materials between the former. Continuously operating dredges can be used for working, the types depending on the thickness of the overburden and the technology to be applied. Deep wells with submerged pumps may be employed for drainage. High-capacity mining districts can be operated at the areas subjected to study, new districts must however be opened up to increase the productive capacity beyond a certain limit. Establishment of a significant power station capacity is made possible by the explored lignite reserves. (In Hungarian)

  1. Mining

    Directory of Open Access Journals (Sweden)

    Khairullah Khan

    2014-09-01

    Full Text Available Opinion mining is an interesting area of research because of its applications in various fields. Collecting opinions of people about products and about social and political events and problems through the Web is becoming increasingly popular every day. The opinions of users are helpful for the public and for stakeholders when making certain decisions. Opinion mining is a way to retrieve information through search engines, Web blogs and social networks. Because of the huge number of reviews in the form of unstructured text, it is impossible to summarize the information manually. Accordingly, efficient computational methods are needed for mining and summarizing the reviews from corpuses and Web documents. This study presents a systematic literature survey regarding the computational techniques, models and algorithms for mining opinion components from unstructured reviews.

  2. Numerical Approach for Goaf-Side Entry Layout and Yield Pillar Design in Fractured Ground Conditions

    Science.gov (United States)

    Jiang, Lishuai; Zhang, Peipeng; Chen, Lianjun; Hao, Zhen; Sainoki, Atsushi; Mitri, Hani S.; Wang, Qingbiao

    2017-11-01

    Entry driven along goaf-side (EDG), which is the development of an entry of the next longwall panel along the goaf-side and the isolation of the entry from the goaf with a small-width yield pillar, has been widely employed in China over the past several decades . The width of such a yield pillar has a crucial effect on EDG layout in terms of the ground control, isolation effect and resource recovery rate. Based on a case study, this paper presents an approach for evaluating, designing and optimizing EDG and yield pillar by considering the results from numerical simulations and field practice. To rigorously analyze the ground stability, the numerical study begins with the simulation of goaf-side stress and ground conditions. Four global models with identical conditions, except for the width of the yield pillar, are built, and the effect of pillar width on ground stability is investigated by comparing aspects of stress distribution, failure propagation, and displacement evolution during the entire service life of the entry. Based on simulation results, the isolation effect of the pillar acquired from field practice is also considered. The suggested optimal yield pillar design is validated using a field test in the same mine. Thus, the presented numerical approach provides references and can be utilized for the evaluation, design and optimization of EDG and yield pillars under similar geological and geotechnical circumstances.

  3. Numerical modeling for longwall pillar design: a case study from a typical longwall panel in China

    Science.gov (United States)

    Zhang, Guangchao; Liang, Saijiang; Tan, Yunliang; Xie, Fuxing; Chen, Shaojie; Jia, Hongguo

    2018-02-01

    This paper presents a new numerical modeling procedure and design principle for longwall pillar design with the assistance of numerical simulation of FLAC3D. A coal mine located in Yanzhou city, Shandong Province, China, was selected for this case study. A meticulously validated numerical model was developed to investigate the stress changes across the longwall pillar with various sizes. In order to improve the reliability of the numerical modeling, a calibration procedure is undertaken to match the Salamon and Munro pillar strength formula for the coal pillar, while a similar calibration procedure is used to estimate the stress-strain response of a gob. The model results demonstrated that when the coal pillar width was 7-8 m, most of the vertical load was carried by the panel rib, whilst the gateroad was overall in a relatively low stress environment and could keep its stability with proper supports. Thus, the rational longwall pillar width was set as 8 m and the field monitoring results confirmed the feasibility of this pillar size. The proposed numerical simulation procedure and design principle presented in this study could be a viable alternative approach for longwall pillar design for other similar projects.

  4. Characterisation of lignite as an industrial adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Ying Qi; Andrew F.A. Hoadley; Alan L. Chaffee; Gil Garnier [Monash University, Clayton, Vic. (Australia). Department of Chemical Engineering

    2011-04-15

    An alternative use of the abundant and inexpensive lignite (also known as brown coal) as an industrial adsorbent has been characterised. The adsorptive properties of two Victorian lignite without any pre-treatment were investigated using the cationic methylene blue dye as a model compound in aqueous solutions. Two commercial activated carbon products were also studied for comparison. The adsorption equilibrium of the four adsorbents was better described by the Langmuir isotherm model than the Freundlich model. The adsorption capacities of the two untreated lignite adsorbents, Loy Yang and Yallourn, calculated using Langmuir isotherms were 286 and 370 mg/g, respectively, higher than a coconut shell-based activated carbon (167 mg/g), but lower than a coal-based activated carbon (435 mg/g). Surface area results suggested that larger micropores and mesopores were important for achieving good methylene blue adsorption by the activated carbons. However, FTIR and cation exchange capacity analyses revealed that, for the lignite, chemical interactions between lignite surface functional groups and methylene blue molecules occurred, thereby augmenting its adsorption capacity. 63 refs., 3 figs., 7 tabs.

  5. A microfluidic device with pillars

    DEFF Research Database (Denmark)

    2014-01-01

    The invention provides a microfluidic device for mixing liquid reagents, the device comprises, a chip forming at least one reaction chamber between a bottom and a top and extending between an inlet and an outlet. To enable manufacturing from less rigid materials, the device comprises pillars...

  6. Integrated analysis of rock mass deformation within shaft protective pillar

    Directory of Open Access Journals (Sweden)

    Ewa Warchala

    2016-01-01

    Full Text Available The paper presents an analysis of the rock mass deformation resulting from mining in the vicinity of the shaft protection pillar. A methodology of deformation prediction is based on a deterministic method using Finite Element Method (FEM. The FEM solution is based on the knowledge of the geomechanical properties of the various geological formations, tectonic faults, types of mining systems, and the complexity of the behaviour of the rock mass. The analysis gave the stress and displacement fields in the rock mass. Results of the analysis will allow for design of an optimal mining system. The analysis is illustrated by an example of the shaft R-VIII Rudna Mine KGHM Polish Copper SA.

  7. Numerical simulation of a multi-reef tabular mining layout in a South African platinum mine

    CSIR Research Space (South Africa)

    Napier, JAL

    2008-09-01

    Full Text Available Some of the key problems facing rock engineers on mines in the Bushveld Complex are design of stable panel spans, optimum pillar dimensions and assessing hangingwall stability. A particularly difficult problem is encountered in some mines where...

  8. Potentials and limitations of spatial and demographic development in Kosovo-Metohija lignite basin

    Directory of Open Access Journals (Sweden)

    Spasić Nenad

    2009-01-01

    Full Text Available The initial research carried out for the purpose of elaborating the Spatial Plan for Kosovo-Metohija Lignite Basin indicated the need to address numerous conflicts and opposing interests in the area concerned. This required the Plan to focus on harmonizing the economic, social and spatial aspects of developing a mining-energy-industrial system (hereinafter MEIS and its surroundings, devising the new ways for the protection of local population interests and use of novel approaches in dealing with the environmental consequences of lignite exploitation and processing. The area wherein Kosovo-Metohija lignite deposits are found is replete with diverse conflicting interests, including insufficient and uneven development, extremely large overall and especially agrarian population density (among the highest in Europe, unemployment and a sizable portion of the grey economy, low level and quality of services of public interest, ethnic conflicts and polarization, etc. The environmental effects of MEIS activities in a situation of this kind were revealed by the early stages of research in all segments of economic, social and spatial development, along with a high degree of environmental degradation. The main conflict in the Plan area is the one between mining and agriculture, i.e. open pit lignite mining and high-fertility soil covering lignite deposits. The conflict is additionally aggravated by the remarkable density of agricultural population on this territory and high selling prices of the land. Therefore, a substantial part of the Plan’s propositions was related to the conditions of settlement and infrastructure relocation, population resettlement and measures to relieve the tensions and prevent the outbreak of potential conflicts in implementing the Plan. The Spatial Plan is conceived as a complex and comprehensive document defining the framework, basic principles, starting points and measures tackling the numerous development conflicts, spatial

  9. Shiftable conveyor systems in open-cast mines in India

    Energy Technology Data Exchange (ETDEWEB)

    Noronha, H S; Patel, J C

    1984-12-01

    The materials handling and earthmoving arrangements are described at the Neyveli lignite mine in Tamil Nadu State, 200 km from Madras, India. The equipment used consists of shiftable conveyors, transfer feeders and drive stations.

  10. Low-temperature carbonization plant for lignite

    Energy Technology Data Exchange (ETDEWEB)

    Shiotsuki, Y

    1949-01-01

    The design and operational data of a low-temperature carbonization plant for Japanese lignite are described. The retort had a vertical cylinder with a capacity of about 10 tons per day. By continuous operation, in which a part of the gas produced was circulated and burned in the lignite zone, about 40 percent semicoke and 3 to 4 percent tar were obtained. From the tar the following products were separated: Low-temperature carbonization cresol, 18.3; motor fuel, 1.00; solvent, 9.97; cresol for medical uses, 11.85; and creosote oil, 32 percent.

  11. Combustion of uraniferous lignites in fluidized bed

    International Nuclear Information System (INIS)

    Morales, G.; Gasos, P.

    1985-01-01

    In this paper a description of the continuous fluid bed combustion pilot plant unit, installed in the Junta de Energia Nuclear facilities, is presented. Besides, this paper deals with some of the studies carried out in the pilot plant aimed at the recovery of uranium from lignites, high in sulfur and ashes, coming from Calaf basin (Barcelona). These studies include the recovery of the heating value of these lignites and the reduction of environmental effect of SO 2 . Based on these studies an application exercise is presented. 9 references, 5 figures, 5 tables

  12. Exploring the impact of reduced hydro capacity and lignite resources on the Macedonian power sector development

    Directory of Open Access Journals (Sweden)

    Taseska-Gjorgievskaa Verica

    2014-01-01

    Full Text Available The reference development pathway of the Macedonian energy sector highlights the important role that lignite and hydro power play in the power sector, each accounting for 40% of total capacity in 2021. In 2030, this dominance continues, although hydro has a higher share due to the retirement of some of the existing lignite plants. Three sensitivity runs of the MARKAL-Macedonia energy system model have been undertaken to explore the importance of these technologies to the system, considering that their resource may be reduced with time: (1 Reducing the availability of lignite from domestic mines by 50% in 2030 (with limited capacity of imports, (2 Removing three large hydro options, which account for 310 MW in the business-as-usual case, and (3 Both of the above restrictions. The reduction in lignite availability is estimated to lead to additional overall system costs of 0.7%, compared to hydro restrictions at only 0.1%. With both restrictions applied, the additional costs rise to over 1%, amounting to 348 M€ over the 25 year planning horizon. In particular, costs are driven up by an increasing reliance on electricity imports. In all cases, the total electricity generation decreases, but import increases, which leads to a drop in capacity requirements. In both, the lignite and the hydro restricted cases, it is primarily gas-fired generation and imports that “fill the gap”. This highlights the importance of an increasingly diversified and efficient supply, which should be promoted through initiatives on renewables, energy efficiency, and lower carbon emissions.

  13. Advanced power assessment for Czech lignite. Task 3.6, Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Sondreal, E.A.; Mann, M.D.; Weber, G.W.; Young, B.C.

    1995-12-01

    The US has invested heavily in research, development, and demonstration of efficient and environmentally acceptable technologies for the use of coal. The US has the opportunity to use its leadership position to market a range of advanced coal-based technologies internationally. For example, coal mining output in the Czech Republic has been decreasing. This decrease in demand can be attributed mainly to the changing structure of the Czech economy and to environmental constraints. The continued production of energy from indigenous brown coals is a major concern for the Czech Republic. The strong desire to continue to use this resource is a challenge. The Energy and Environmental Research Center undertook two major efforts recently. One effort involved an assessment of opportunities for commercialization of US coal technologies in the Czech Republic. This report is the result of that effort. The technology assessment focused on the utilization of Czech brown coals. These coals are high in ash and sulfur, and the information presented in this report focuses on the utilization of these brown coals in an economically and environmentally friendly manner. Sections 3--5 present options for utilizing the as-mined coal, while Sections 6 and 7 present options for upgrading and generating alternative uses for the lignite. Contents include Czech Republic national energy perspectives; powering; emissions control; advanced power generation systems; assessment of lignite-upgrading technologies; and alternative markets for lignite.

  14. Controlled Roof Collapse during Secondary Mining in Coal Mines

    Directory of Open Access Journals (Sweden)

    Ashleigh Hutchinson

    2012-01-01

    Full Text Available The problem considered is an investigation of the possible collapse of the roof between the pillar next to be mined in secondary coal mining and the first line of pillar remnants called snooks. The roof rock between the pillar, which is the working face, and the snook is modelled as an Euler-Bernoulli beam acted on at each end by a horizontal force and by its weight per unit length. The beam is clamped at the pillar and simply supported (hinged at the snook. The dimensionless differential equation for the beam and the boundary conditions depend on one dimensionless number . We consider the range of values of before the displacement and curvature first become singular at =1. The model predicts that for all practical purposes, the beam will break at the clamped end at the pillar. The failure of the beam for values of greater than 1 is investigated computationally.

  15. Briquetting of Tuncbilek lignite fines by using ammonium nitrohumate as a binder

    Energy Technology Data Exchange (ETDEWEB)

    Yildirim, M.; Ozbayoglu, G. [Cukurova University, Adana (Turkey). Mining Engineering Dept.

    2004-03-01

    Results of experiments on the briquetting of Tuncbilek lignite fines using ammonium nitrohumate (anh), a low calorific value, young lignite-derived humic acid salt solution, are reported. The particulate material was blended with ammonium nitrohumate serving as the binder. In the briquetting tests, the effects of moisture content, pressure, binder content, nitrogen content and heat treatment were investigated. Durable briquettes, in terms of mechanical strength and water resistance, were produced with a 7% binder content at 10.5% moisture, following pressing at 1280 kg/cm{sup 2} and drying at 165{sup o}C for 1 h. The briqueues produced with ammonium nitrohumate had better combustion properties than run-of-mine samples; the contribution of the binder to smoke and sulphur emissions was very low and fine dust particles were negligible.

  16. 12th International Symposium Continuous Surface Mining

    CERN Document Server

    2015-01-01

    This edited volume contains research results presented at the 12th International Symposium Continuous Surface Mining, ISCSM Aachen 2014. The target audience primarily comprises researchers in the lignite mining industry and practitioners in this field but the book may also be beneficial for graduate students.

  17. Spatiotemporal mapping of ground water pollution in a Greek lignite basin, using geostatistics

    International Nuclear Information System (INIS)

    Modis, K.

    2010-01-01

    An issue of significant interest in the mining industry in Greece is the occurrence of chemical pollutants in ground water. Ammonium, nitrites and nitrates concentrations have been monitored through an extensive sampling network in the Ptolemais lignite opencast mining area in Greece. Due to intensive mining efforts in the area, the surface topology is continuously altered, affecting the life span of the water boreholes and resulting in messy spatiotemporal distribution of data. This paper discussed the spatiotemporal mapping of ground water pollution in the Ptolemais lignite basin, using geostatistics. More specifically, the spatiotemporal distribution of ground water contamination was examined by the application of the bayesian maximum entropy theory which allows merging spatial and temporal estimations in a single model. The paper provided a description of the site and discussed the materials and methods, including samples and statistics; variography; and spatiotemporal mapping. It was concluded that in the case of the Ptolemais mining area, results revealed an underlying average yearly variation pattern of pollutant concentrations. Inspection of the produced spatiotemporal maps demonstrated a continuous increase in the risk of ammonium contamination, while risk for the other two pollutants appeared in hot spots. 18 refs., 1 tab., 7 figs.

  18. Spatiotemporal mapping of ground water pollution in a Greek lignite basin, using geostatistics

    Energy Technology Data Exchange (ETDEWEB)

    Modis, K. [National Technical Univ. of Athens, Athens (Greece)

    2010-07-01

    An issue of significant interest in the mining industry in Greece is the occurrence of chemical pollutants in ground water. Ammonium, nitrites and nitrates concentrations have been monitored through an extensive sampling network in the Ptolemais lignite opencast mining area in Greece. Due to intensive mining efforts in the area, the surface topology is continuously altered, affecting the life span of the water boreholes and resulting in messy spatiotemporal distribution of data. This paper discussed the spatiotemporal mapping of ground water pollution in the Ptolemais lignite basin, using geostatistics. More specifically, the spatiotemporal distribution of ground water contamination was examined by the application of the bayesian maximum entropy theory which allows merging spatial and temporal estimations in a single model. The paper provided a description of the site and discussed the materials and methods, including samples and statistics; variography; and spatiotemporal mapping. It was concluded that in the case of the Ptolemais mining area, results revealed an underlying average yearly variation pattern of pollutant concentrations. Inspection of the produced spatiotemporal maps demonstrated a continuous increase in the risk of ammonium contamination, while risk for the other two pollutants appeared in hot spots. 18 refs., 1 tab., 7 figs.

  19. Coal mining situation in the Federal Republic of Germany. The 1st quarter 2016; Zur Lage des Kohlenbergbaus in der Bundesrepublik Deutschland. 1. Vierteljahr 2016

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-06-06

    The paper reports on the coal mining in the Federal Republic of Germany in the 1st quarter of 2016. Statistical data are presented for mining, exports and imports of hard coal and lignite and for employees.

  20. Coal mining situation in the Federal Republic of Germany. The 1st quarter 2015; Zur Lage des Kohlenbergbaus in der Bundesrepublik Deutschland. 1. Vierteljahr 2015

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-07-07

    The paper reports on the coal mining in the Federal Republic of Germany in the 1st quarter of 2015. Statistical data are presented for mining, exports and imports of hard coal and lignite and for employees.

  1. Coal mining situation in the Federal Republic of Germany. The 1st quarter 2017; Zur Lage des Kohlenbergbaus in der Bundesrepublik Deutschland. 1. Vierteljahr 2017

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2017-06-14

    The paper reports on the coal mining in the Federal Republic of Germany in the 1st quarter of 2017. Statistical data are presented for mining, exports and imports of hard coal and lignite and for employees.

  2. Causes of falls of hangingwall over gullies adjacent to stabilizing strike pillars

    CSIR Research Space (South Africa)

    Turner, PA

    1987-08-01

    Full Text Available This report discusses the occurrence of falls of ground in strike gullies. Falls of hangingwall over strike gullies on the up-dip side of strike stabilizing pillars in longwall mining systems were investigated. Gullies were examined in both...

  3. Concentration of heavy metals and trace elements in soils, waters and vegetables and assessment of health risk in the vicinity of a lignite-fired power plant

    Energy Technology Data Exchange (ETDEWEB)

    Noli, Fotini, E-mail: noli@chem.auth.gr; Tsamos, Panagiotis, E-mail: pktsamos@chem.auth.gr

    2016-09-01

    The pollution of agricultural soils, waters and products in the regions of lignite mines and fired power plants is of great importance. The concentration of As, Βa, Co, Cr, Sr, Sc, Th, U, Zn in soils and waters in the vicinity of a lignite-fired power plant in Northern Greece was determined using Instrumental Neutron Activation Analysis. The determination frequency was every three months during a period of one year in order to evaluate the seasonal impact of the pollution to the environment. Measurements were performed in three locations around the lignite mine as well as in one reference location at a certain distance from the mine. The results, which exhibited a slight seasonal variation, were compared, where possible, with literature values from other countries. The obtained data in most of the cases did not exceed the normal levels and indicated that the investigated area was only slightly contaminated. The concentration of heavy and trace metals was also measured in three common garden crops (tomato, cucumber and parsley) grown in this area. The calculated transfer factors (TF) from soil to vegetables and health risk quotients (HQ) do not denote a health risk. - Highlights: • Seasonal variation of heavy metals concentrations in soils and waters in a lignite mining area. • The elevated concentrations detected by NAA indicating minor contamination of the studied area. • Determination of minor and trace elements in vegetables. • The transfer factors and health risk quotients indicating a possible slight contamination in the area.

  4. Concentration of heavy metals and trace elements in soils, waters and vegetables and assessment of health risk in the vicinity of a lignite-fired power plant

    International Nuclear Information System (INIS)

    Noli, Fotini; Tsamos, Panagiotis

    2016-01-01

    The pollution of agricultural soils, waters and products in the regions of lignite mines and fired power plants is of great importance. The concentration of As, Βa, Co, Cr, Sr, Sc, Th, U, Zn in soils and waters in the vicinity of a lignite-fired power plant in Northern Greece was determined using Instrumental Neutron Activation Analysis. The determination frequency was every three months during a period of one year in order to evaluate the seasonal impact of the pollution to the environment. Measurements were performed in three locations around the lignite mine as well as in one reference location at a certain distance from the mine. The results, which exhibited a slight seasonal variation, were compared, where possible, with literature values from other countries. The obtained data in most of the cases did not exceed the normal levels and indicated that the investigated area was only slightly contaminated. The concentration of heavy and trace metals was also measured in three common garden crops (tomato, cucumber and parsley) grown in this area. The calculated transfer factors (TF) from soil to vegetables and health risk quotients (HQ) do not denote a health risk. - Highlights: • Seasonal variation of heavy metals concentrations in soils and waters in a lignite mining area. • The elevated concentrations detected by NAA indicating minor contamination of the studied area. • Determination of minor and trace elements in vegetables. • The transfer factors and health risk quotients indicating a possible slight contamination in the area.

  5. Organically pillared layered zinc hydroxides

    International Nuclear Information System (INIS)

    Kongshaug, K.O.; Fjellvaag, Helmer

    2004-01-01

    The two organically pillared layered zinc hydroxides [Zn 2 (OH) 2 (ndc)], CPO-6, and [Zn 3 (OH) 4 (bpdc)], CPO-7, were obtained in hydrothermal reactions between 2,6-naphthalenedicarboxylic acid (ndc) and zinc nitrate (CPO-6) and 4,4'biphenyldicarboxylate (bpdc) and zinc nitrate (CPO-7), respectively. In CPO-6, the tetrahedral zinc atoms are connected by two μ 2 -OH groups and two carboxylate oxygen atoms, forming infinite layers extending parallel to the bc-plane. These layers are pillared by ndc to form a three-dimensional structure. In CPO-7, the zinc hydroxide layers are containing four-, five- and six coordinated zinc atoms, and the layers are built like stairways running along the [001] direction. Each step is composed of three infinite chains running in the [010] direction. Both crystal structures were solved from conventional single crystal data. Crystal data for CPO-6: Monoclinic space group P2 1 /c (No. 14), a=11.9703(7), b=7.8154(5), c=6.2428(4) A, β=90.816(2) deg., V=583.97(6) A 3 and Z=4. Crystal data for CPO-7: Monoclinic space group C2/c (No. 15), a=35.220(4), b=6.2658(8), c=14.8888(17) A, β=112.580(4) deg., V=3033.8(6) A 3 and Z=8. The compounds were further characterized by thermogravimetric- and chemical analysis

  6. Production of heavy greases from lignite

    Energy Technology Data Exchange (ETDEWEB)

    1921-03-18

    A process is described for the extraction of heavy greases and wagon greases and their equivalents, by separation from bitumins, resins, and waxes contained in lignite, peat, bituminous shale, fossil wax, paraffin, etc., characterized by the fact that for the extraction are used solvents of high boiling point, such as mineral oils, grease oils, tar oils, and other equivalents, which are not eliminated and at the same time constitute a part of the product obtained.

  7. The German lignite industry. Historical development, resources, technology, economic structures and environmental impact. Study; Die deutsche Braunkohlenwirtschaft. Historische Entwicklungen, Ressourcen, Technik, wirtschaftliche Strukturen und Umweltauswirkungen. Studie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2017-05-15

    Lignite has a key role to play in the transformation of the energy system due to its specific structural features in terms of industry, company history, policy, economics, the environment and regional structures. Understanding these structural features of the German lignite industry is an important requirement for classifying the significance of the lignite industry up to now and for the redesigning of this industrial sector. From these environmental, economic and regulatory structural characteristics, which are interwoven in a variety of ways, the incentives arise for the mining and power plant operators to react to energy price signals or energy policy steering. The aim of this research study is to define these structural features, to compile comprehensively the basic data and information that is not always transparently available, to understand the interactions, to enable the navigation of issues that are partly very complex, and to classify into the long-term developments that are especially important for political and social processes. In 2016 approx. 12 percent of German primary energy consumption was met using lignite. At the same time, lignite has the highest carbon dioxide (CO2) emissions of the fossil fuels; it currently accounts for approx. 19 percent of Germany's total greenhouse gas emissions as well as approx. 46 percent of the total CO2 emissions of the electricity sector. As a result of the mining of lignite and its conversion into electricity, substantial adverse impacts beyond the entry of greenhouse gases into the Earth's atmosphere arise for other environmental media. These impacts include half of Germany's mercury emissions, approx. a third of its sulfur dioxide emissions and approx. a tenth of its nitrogen oxide emissions. Lignite mining in open-cast mines takes up a substantial amount of landscape and soil and requires huge interventions in the water balance. Relatively high costs arise for the recultivation and rehabilitation

  8. Petrographic Composition of Lignite from the Lake Somerville Spillway (East-central Texas)

    Science.gov (United States)

    Pawelec, Sandra; Bielowicz, Barbara

    2017-12-01

    Jackson Group, namely Gibbons Creek and San Miguel lignite mines.

  9. An overview of underground coal gasification and its applicability for Turkish lignite

    Energy Technology Data Exchange (ETDEWEB)

    Pekpak, E.; Yoncaci, S.; Kilic, M.G. [Middle East Technical Univ., Ankara (Turkey). Dept. of Mining Engineering

    2010-07-01

    Coal is expected to maintain its significance as an energy source for a longer time period than oil and natural gas. Environmental concerns have led to the development of clean coal technologies, such as coal gasification. Coal gasification can be used at either at surface or in underground coal gasification (UCG). UCG has several advantages over surface gasification and conventional mining such as rank low calorific value coals. Coal gasification also has the potential to contribute to the energy supply of a country. Most Turkish coals are lignite and UCG may enable diversification of energy sources of Turkey and may help decrease external dependency on energy. This paper presented a study that matched a UCG technique to the most appropriate (Afsin Elbistan) lignite reserve in Turkey. Two UCG techniques were presented, including the linked vertical well method, and the directional drilling-controlled retractable injection point (CRIP) method. The properties of coal seams and coal properties were also outlined. It was concluded that Cobanbey is the most preferable sector in the Elbistan Lignite Reserve for a pilot study, and that the linked vertical well method could be considered as a candidate method. 17 refs., 6 tabs., 1 fig.

  10. Suspension of Water Droplets on Individual Pillars

    DEFF Research Database (Denmark)

    Tóth, T.; Ferraro, D.; Chiarello, E.

    2011-01-01

    We report results of extensive experimental and numerical studies on the suspension of water drops deposited on cylindrical pillars having circular and square cross sections and different wettabilities. In the case of circular pillars, the drop contact line is pinned to the whole edge contour unt...

  11. Reassessment of coal pillar design procedure

    CSIR Research Space (South Africa)

    Madden, BJ

    1995-12-01

    Full Text Available The SIMRAC project COL 021A entitled “a reassessment of coal pillar design procedures” set out to achieve a coal pillar design procedure that takes cognisance of different geological and structural factors as well as the influence...

  12. Carbonate and lignite cycles in the Ptolemais Basin: Orbital control and suborbital variability (Late Neogene, northern Greece)

    Science.gov (United States)

    Weber, M. E.; Tougiannidis, N.; Ricken, W.; Rolf, C.; Kleineder, M.; Bertram, N.; Antoniadis, P.

    2009-04-01

    We recently commenced a project to investigate deep drillings as well as outcrops in the Ptolemais Basin, northern Greece, for paleoenvironmental and paleoclimate change. Specific attention is paid to mining sites Achlada, Vevi, Vegora, Amynteon, North Field, South Field, and Lava. The sediment archive comprises Upper Miocene to Quaternary continental lake deposits (up to 800 m thick) with an extended Lower Pliocene section. The Upper Miocene sections are composed of diatomaceous mud and gray marls. Pliocene lake sediments commence with the Kyrio member (lignite/grey marl), followed by the Theodoxus member (beige marl/lignite), and the Notio member (marl with intercalated sand /lignite). The limnic deposits show striking rhythmic bedding of (mostly) carbonates and lignites, reflecting orbital-induced humidity and temperature changes in this small NW-SE elongated continental basin. First, we retrieved chronometric information by determining magnetic polarity changes on three sites as independent stratigraphic ground-truth in combination with palynological evidence and published data. Then we conducted a number of high-resolution (1 - 6 cm increment), non-destructive measurements to obtain paleoclimate proxies: photospectrometry (colors L, a, b), magnetic susceptibility, and natural gamma. Accordingly, we achieved a multi-proxy insight into paleoclimate and paleoenvironmental evolution at unprecedented temporal resolution (up to a few decades!) over long time series and at a number of key sites. Using the newly-developed ESALab software, we conducted spectral and evolutionary spectral analysis to evaluate the cyclo-stratigraphic development. As for orbital variability, spectral power is concentrated on precession, hemi-precession, and eccentricity, with only minor impact of orbital tilt. We used this information to increase the temporal resolution of our age models by tuning as many precession (insolation) maxima as possible to carbonate minima (lignite maxima

  13. Natural radioisotopes in lignite of the Ptolemais region (Greece) and in their ashes

    International Nuclear Information System (INIS)

    Simopoulos, S.E.; Angelopoulos, M.G.

    1987-01-01

    Samples of lignite, fly ash and bottom ash of a power plant, located in the Ptolemais region, were examined by gamma spectroscopy and their concentrations in Ra-226, Ra-228 and K-40 have been determined. These samples were prepared from samples taken daily for a period of one month. The brown coal samples are taken from the front of the brown coal field supplying one of the units. They show a flutuation of the concentrations of the same radionuclides in the brown coal seams and in the intermediate layers. Further samples taken from 3 small private mines of the Ptolemais region were also examined. (author)

  14. Thermoelectric properties of silicon nano pillars

    Energy Technology Data Exchange (ETDEWEB)

    Stranz, Andrej; Soekmen, Uensal; Waag, Andreas; Peiner, Erwin [Institute of Semiconductor Technology, Braunschweig (Germany)

    2010-07-01

    In order to establish silicon as a efficient thermoelectric material, its high thermal conductivity has to be reduced which is feasible, e.g., by nano structuring. Therefore, in this study Si-based sub-micron pillars of various dimensions were investigated. Using anisotropic etching followed by thermal oxidation we could fabricate pillars of diameters <500 nm, about 25 {mu}m in height with aspect ratios of more than 50. The distance between the pillars was varied from 500 nm to 10 micron. Besides the fabrication and structural characterization of sub-micron silicon pillars, and adequate metrology for measuring their thermoelectric properties was implemented. Commercial tungsten probes and self-made gold probes, as well as Wollaston wire probes were used for electrical and thermal conductivity, as well as Seebeck voltage measurements on single pillars in a scanning electron microscope equipped with nano manipulators.

  15. Comparative palynology of clastics and lignites from the Manning Formation, Jackson Group, Upper Eocene, Grimes County, TX

    Energy Technology Data Exchange (ETDEWEB)

    Gennett, J.A. [Texas A& M Univ., College Station, TX (United States)

    1996-09-01

    The 3500 lignite seam at the Gibbons Creek Mine in Grimes County, TX was sampled for pollen and spores at 10 cm intervals. The majority of samples are dominated (to 60%) by Momipites from the Juglandaceae (walnut family), as is typical of Jackson Group sediments. Other palynomorph taxa vary systematically, with a peak of pollen of the freshwater tree Nyssa (blackgum) and associated Rboipites angustus (to 17%) occurring at the base. Higher in the seam, increase (to 55%) of Cupuliferoipollenites (a chestnut-like grain) and Cyrillaceae-pollenites? ventosus (to 7%) percentages may indicate a higher salinity environment. A Chrysophyllum (satin leaf) peak (to 25%) near the top of the seam suggests relatively shallow fresh-water conditions. Core samples from an interval above the lignites represent a transgressive-regressive cycle in inner shelf clastics. These samples were taken at 40 cm or greater intervals and reveal the regional pollen flora. Although minor changes occur, palynomorph spectra are for the most part homogenous. The dominant grain is again Momipites coryloides, but in general percentages are lower (to 35%). Cupuliferoipollenites (to 17%), Chrysophyllum (to 5%), and Rhoipites angustus (to 3%) are not less important, but do not peak as they do in the lignite spectra. Palm leaf megafossils; in one sample suggest a clastic wetland; in this sample palm pollen (mostly Arecipites, representing the modern saw palmetto) reaches 73%. Another sample contains high (26%) percentages of the fern spore Lygodiumsporites adriennis. High percentages of these two taxa do not occur in the lignite samples.

  16. Review of fill mining technology in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Singh, K. H.; Hedley, D. G.F.

    1980-05-15

    The Canadian mining industry has a long history of being in the fore-front in developing new technology in underground hardrock mines. Examples include the development of hydraulic and cemented fills, undercut-and-fill, mechanized cut-and-fill, post pillar, vertical retreat and blasthole mining methods. The evolution of this technology is briefly described in an historical review. Backfill serves many functions, although it is generally considered in terms of its support capabilities. These functions, mainly related to the mining method used, are evaluated in regard to regional support, pillar support, fill roof, working floor, dilution control and waste disposal. With the advent of blasthole and vertical retreat methods for pillar recovery operations, the freestanding height of backfill walls has assumed greater importance. Consequently, more attention is being given to what fill properties are required to achieve fill wall exposures up to 25 m wide by 90 m high. With the large increases in energy costs, alternatives to partially replace Portland cement in fill are being examined. The validation of mining concepts and the interaction of backfill is perhaps best evaluated by in-situ measurements. Examples are given of stress, deformation and fill pressure measurements in longitudinal cut-and-fill, post pillar mining and blasthole stoping with delayed fill which were taken in several mines in Canada. Finally, the overall design procedure used in deciding mining method, stope and pillar dimensions, sequence of extraction, fill properties and support systems at a new mine is described.

  17. Pillar support for a wind power plant

    Energy Technology Data Exchange (ETDEWEB)

    Dietz, A

    1978-08-24

    The invention concerns a stationary pillar for a wind power plant with vertical rotors in the outside walls of individual parts of the structure, which are arranged above one antoher and which can turn together freely as a pillar facade. There are problems in such a stationary pillar because of storm forces on the one hand, which try to buckle the pillar, and, on the other hand, the pillar should be easy to mount without difficult fishplates or screwed connections. In order to solve this problem, the invention provides that tension elements run from the top ring of the pillar to the foundation through all the spars and through the connecting rings inside the spars, whose tension forces not only counteract buckling of the pillar, but also pull the intersections of the spars together in tension and independently of the screwed connections also provided. The connecting rings at the connections to the spars have half sleeves, which are pushed into a sleeve of the spar coming from below. The tension elements can consist of bundles of steel wires or a wire rope.

  18. Use of D8K's at the Arjuzanx lignite mine

    Energy Technology Data Exchange (ETDEWEB)

    1978-11-01

    Gives a general account of the Arjuzanx opencast site, Landes, which supplies a 245 MW thermal power station. Describes the special use of Caterpillar machines: three D8's for loading out of dirt under the stacker at the rate of 2500 t/hour, over a maximum distance of 120 m and two D8H's with three D8K tractors, fitted with a special device for snaking the conveyor forward. The drivers' cabs are sound-proofed and air-conditioned.

  19. The need for verification of the Polish lignite deposits owing to development and nature conservation protection on land at the surface

    Directory of Open Access Journals (Sweden)

    Naworyta Wojciech

    2016-12-01

    Full Text Available Poland is a country rich in lignite. The area where the lignite occurs occupies approx. 22% of the total surface area of the country. Geological resources of Polish lignite deposits are estimated at 23.5 billion Mg, but in the majority (69% the accuracy of their identification is poor. Nevertheless the amount of coal in Polish deposits allows - at least in theory - for mining and energy production at the current level for hundreds of years to come. It is an important raw material for the energy security of the country both currently and in the future. Because the vast majority of Polish and foreign mines use an open pit method for lignite extraction the actual amount of mineral available for the extraction depends not only on the properties of the deposit but to a large extent on the method of development of the surface land above the deposit, as well as on the sensitivity of the environment in the vicinity of any future mines. After careful analysis it can be stated that only a few of the lignite deposits may be subject to cost-effective mining operations. These deposits should be subjected to special protection as a future resource base which will ensure the energy security of the country. Some examples of domestic deposits have been presented where due to the conflict resulting from the development of the area should be deleted from the Balance Sheet of Mineral Deposits because their exploitation is irrational and uneconomic. Keeping such deposits in the Balance Sheet, and the use of large numbers in the context of their resource base leads to an unwarranted sense of wealth which consequently does not encourage the protection of these deposits which may actually be subject to rational exploitation in the near future. In summary there is a need to find a compromise in order to adequately protect all natural resources including mineral deposits.

  20. Design of Merensky Reef crush pillars

    CSIR Research Space (South Africa)

    Watson, BP

    2010-10-01

    Full Text Available appear stiff enough. However, evidence from the pillar bursts suggests that unfailed pillars located at 10 m or more from the face are in a dangerous, soft-loading situation and may burst if failure takes place. From the evidence of the few collapses... reached a deformation of 32 mm during the initial failure and all failed in a reasonably stable manner. The unacceptable stiffness of the surrounding strata is about 5.0 mm/GN. Most of the measured pillars failed under loading conditions where...

  1. PEDOT pillar fabrication using DOD inkjet system

    Science.gov (United States)

    Cui, Wei; Chang, Cheng-Ling; Wang, Wei-Chih

    2012-04-01

    In this paper, we present our preliminary results of high aspect ratio 3D PEDOT pillar study by drop-on demand (DOD) direct printing system. Design of the experimental setup and the fabrication of the DOD PEDOT pillar are introduced. Currently, the system can achieve a PEDOT pillar with a height of 300 μm and 80 μm in diameter. The proposed PEDOT 3D printing process has a wide range of potential applications in the eletronics and display industry.

  2. Preparation and combustion of Yugoslavian lignite-water fuel, Task 7.35. Topical report, July 1991--December 1993

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, C.M.; DeWall, R.A.; Ljubicic, B.R.; Musich, M.A.; Richter, J.J.

    1994-03-01

    Yugoslavia`s interest in lignite-water fuel (LWF) stems from its involvement in an unusual power project at Kovin in northern Serbia. In the early 1980s, Electric Power of Serbia (EPS) proposed constructing a 600-MW power plant that would be fueled by lignite found in deposits along and under the Danube River. Trial underwater mining at Kovin proved that the dredging operation is feasible. The dredging method produces a coal slurry containing 85% to 90% water. Plans included draining the water from the coal, drying it, and then burning it in the pulverized coal plant. In looking for alternative ways to utilize the ``wet coal`` in a more efficient and economical way, a consortium of Yugoslavian companies agreed to assess the conversion of dredged lignite into a LWF using hot-water-drying (HWD) technology. HWD is a high-temperature, nonevaporative drying technique carried out under high pressure in water that permanently alters the structure of low-rank coals. Changes effected by the drying process include irreversible removal of moisture, micropore sealing by tar, and enhancement of heating value by removal of oxygen, thus, enhancement of the slurry ability of the coal with water. Physical cleaning results indicated a 51 wt % reduction in ash content with a 76 wt % yield for the lignite. In addition, physical cleaning produced a cleaned slurry that had a higher attainable solids loading than a raw uncleaned coal slurry. Combustion studies were then performed on the raw and physically cleaned samples with the resulting indicating that both samples were very reactive, making them excellent candidates for HWD. Bench-scale results showed that HWD increased energy densities of the two raw lignite samples by approximately 63% and 81%. An order-of-magnitude cost estimate was conducted to evaluate the HWD and pipeline transport of Kovin LWF to domestic and export European markets. Results are described.

  3. COFIRING BIOMASS WITH LIGNITE COAL; FINAL

    International Nuclear Information System (INIS)

    Darren D. Schmidt

    2002-01-01

    The University of North Dakota Energy and Environmental Research Center, in support of the U.S. Department of Energy's (DOE) biomass cofiring program, completed a Phase 1 feasibility study investigating aspects of cofiring lignite coal with biomass relative to utility-scale systems, specifically focusing on a small stoker system located at the North Dakota State Penitentiary (NDSP) in Bismarck, North Dakota. A complete biomass resource assessment was completed, the stoker was redesigned to accept biomass, fuel characterization and fireside modeling tests were performed, and an engineering economic analysis was completed. In general, municipal wood residue was found to be the most viable fuel choice, and the modeling showed that fireside problems would be minimal. Experimental ash deposits from firing 50% biomass were found to be weaker and more friable compared to baseline lignite coal. Experimental sulfur and NO(sub x) emissions were reduced by up to 46%. The direct costs savings to NDSP, from cogeneration and fuel saving, results in a 15- to 20-year payback on a$1,680,000 investment, while the total benefits to the greater community would include reduced landfill burden, alleviation of fees for disposal by local businesses, and additional jobs created both for the stoker system as well as from the savings spread throughout the community

  4. Coal mine subsidence and structures

    International Nuclear Information System (INIS)

    Gray, R.E.

    1988-01-01

    Underground coal mining has occurred beneath 32 x 10 9 m 2 (8 million acres) of land in the United States and will eventually extend beneath 162 x 10 9 m 2 (40 million acres). Most of this mining has taken place and will take place in the eastern half of the United States. In areas of abandoned mines where total extraction was not achieved, roof collapse, crushing of coal pillars, or punching of coal pillars into softer mine floor or roof rock is now resulting in sinkhole or trough subsidence tens or even hundreds of years after mining. Difference in geology, in mining, and building construction practice between Europe and the United States preclude direct transfer of European subsidence engineering experience. Building damage cannot be related simply to tensile and compressive strains at the ground surface. Recognition of the subsidence damage role played by ground-structure interaction and by structural details is needed

  5. The effect of environmental pollution on the respiratory system of lignite miners: a diachronic study.

    Science.gov (United States)

    Sichletidis, L; Tsiotsios, I; Chloros, D; Daskalopoulou, E; Ziomas, I; Michailidis, K; Kottakis, I; Konstantinidis, T H; Palladas, P

    2004-01-01

    It is not known whether working in surface lignite mines can cause x-ray lesions or disorders of respiratory function. The aim of the study was to investigate the diachronic impact of environmental pollution on the respiratory system of lignite miners at mines in Eordea, Greece. Cases of 199 workers (Group A) residing permanently in the Eordea valley and 151 (Group B) living outside the Eordea valley were studied during Phase I and then re-examined after three years (Phase II). These cases were compared to those of 71 office workers living in Eordea valley (Group C) and to 96 living in Grevena, a region without pollution (Group D). The study included the completion of the MRC questionnaire for the detection of respiratory diseases, pulmonary function tests, measurement of diffusion capacity, otorhinolaryngologic examination, rhinomanonetry as well as chest and paranasal cavity X-rays. Chronic bronchitis was reported by 26.8%, 24.8%, 17.9% and 10.6% respectively of the subjects of groups A, B, C and D according to the answers of the questionnaire (pmines under conditions of excessive pollution by airborne contaminants have a high prevalence of atrophic rhinitis and, in addition to other standard examinations, should undergo rhinomanometry testing and X-ray imaging of the paranasal cavities.

  6. The Three Pillars of Machine Programming

    OpenAIRE

    Gottschlich, Justin; Solar-Lezama, Armando; Tatbul, Nesime; Carbin, Michael; Rinard, Martin; Barzilay, Regina; Amarasinghe, Saman; Tenenbaum, Joshua B; Mattson, Tim

    2018-01-01

    In this position paper, we describe our vision of the future of machine programming through a categorical examination of three pillars of research. Those pillars are: (i) intention, (ii) invention, and(iii) adaptation. Intention emphasizes advancements in the human-to-computer and computer-to-machine-learning interfaces. Invention emphasizes the creation or refinement of algorithms or core hardware and software building blocks through machine learning (ML). Adaptation emphasizes advances in t...

  7. Discussing three pillars of corporate governance

    OpenAIRE

    Andrei STĂNCULESCU; Eugen MITRICĂ

    2015-01-01

    This paper is a meaningful attempt to critically analyze the cohesion and relationship between three fundamental pillars of the corporate governance system: the shareholders, the board of directors and the employees. We present the characteristics of each pillar and discuss its relevance in corporate governance. A couple of world-renowned corporate governance models are considered. A synthetic conclusion is drawn based on information presented.

  8. Perspectives on the German lignite industry in 2012. Stability through diversity; Perspektiven der deutschen Braunkohlenindustrie 2012. Stabilitaet durch Vielfalt

    Energy Technology Data Exchange (ETDEWEB)

    Lambertz, Johannes F. [RWE Power AG, Koeln (Germany); Milojcic, George [Bundesverband Braunkohle (DEBRIV), Koeln (Germany)

    2012-07-15

    tomorrow. In this respect, by including the interests of our partners and neighbours, and also of our employees, we will go on justifying the confidence placed in us in the various mining areas by the public and by decision-takers. We are keenly aware that dependability and a fair balancing of interests is the basis of any successful cooperation. Experience has shown that the lignite industry can prepare for new challenges. Ahead of us is an ambitious road that we can take with optimism and self-confidence. In my opinion, this includes a duty to provide a committed input to the debate surrounding our future. Good Luck.. or as we say in our industry: Glueckauf. (orig.)

  9. Biosolubilization of raw and gamma irradiated lignite by trichoderma asperellum

    International Nuclear Information System (INIS)

    Sugoro, I.; Astuti, D.I.; Aditiawati, P.; Sasongko, D.

    2012-01-01

    Biosolubilization is a promising technology for converting solid coal to liquid oil by addition of microorganism. Aim of this research is to compare between gamma irradiated lignite (10 kGy) with raw lignite in biosolubilization by selected fungi Trichoderma asperellum. Treatments were A (MSS + gamma irradiated lignite 5% + T. asperellum) and B (MSS + raw lignite 5% + T. asperellum) with sub-merged culture. There were two parameters observed i.e. biosolubilization product based on absorbance value at λ 250nm and λ 450nm and metal analysis by neutron activation analysis (NAA). The highest biosolubilization will be analyzed by FTIR and GCMS. The results showed that biosolubilization of raw lignite (B) was higher than sterilized lignite (A) based on absorbance value at λ 250nm and λ 450nm . The metal of lignite was decreased after incubation. FTIR analysis showed that both of treatment had similar spectra on biosolubilization products. GCMS analysis showed that both of treatment had different number of hydrocarbon, i.e. C 6 - C 35 (A) and C 10 - C 35 (B) and dominated by aromatic acids, aliphatic and phenylethers. Both of treatment product had the potency as oil substituted but its recommended to deoxygenate for higher quality. (author)

  10. Imaging of the cervical articular pillar

    Energy Technology Data Exchange (ETDEWEB)

    Yeomans, E. [Orange Base Hospital, Orange, NSW (Australia)

    1998-12-01

    The cervical articular pillar, due to the complex anatomical structure of the cervical spine, is not well demonstrated in routine plain radiographic views. Dedicated views have been devised to demonstrate the pillar, yet their performance has abated considerably since the inception of Computed Tomography (CT) in the 1970`s. It is the consideration that CT does not image the articular pillar with a 10 per cent accuracy that poses the question: Is there still a need for plain radiography of the cervical articular pillar? This paper studies the anatomy, plain radiography, and incidence of injury to the cervical articular pillar. It discusses (with reference to current and historic literature) the efficacy of current imaging protocols in depicting this injury. It deals with plain radiography, CT, complex tomography, and Magnetic Resonance Imaging (MRI) of the cervical spine to conclude there may still be a position in current imaging protocols for plain radiography of the cervical articular pillar. Copyright (1998) Australian Institute of Radiography 43 refs., 5 figs.

  11. Pillar size optimization design of isolated island panel gob-side entry driving in deep inclined coal seam—case study of Pingmei No. 6 coal seam

    Science.gov (United States)

    Zhang, Shuai; Wang, Xufeng; Fan, Gangwei; Zhang, Dongsheng; Jianbin, Cui

    2018-06-01

    There is a perception that deep roadways are difficult to maintain. To reverse this and to improve the recovery rate of coal resources, gob-side entry driving is widely used in coal mines, especially deep-mining coal mines, in China. Determination of the reasonable pillar size through in situ observation and experimentation plays a vital role for roadway maintenance. Based on the geological conditions of Pingmei No.6 coal seam, a theoretical analysis, numerical simulation, and industrial experiments are carried out to calculate the reasonable width of chain pillars, analyze the lateral support stress distribution law near the gob side, investigate the relationship between the coal pillar stress distribution, roadway surrounding rock stress distribution, roadway surrounding rock deformation and the coal pillar width. The results indicate that 5 m wide coal pillars can ensure that the chain pillars are at a lower stress level and the deformation of roadway surrounding rock is in a more reasonable range. Industrial experiments show that when the chain pillar width is 5 m, the deformation of roadway surrounding rock can meet the requirements of working face safe production. The numerical results agreed well with field measurement and observations, and the industrial experiments results further validated the results of the numerical simulation.

  12. Use of abandoned coal/lignite open pits for waste disposal in selected European countries

    International Nuclear Information System (INIS)

    Libicki, J.S.

    1989-01-01

    The use of abandoned coal/lignite pits as disposal sites for solid waste appears to be a reasonable approach to a difficult problem, especially if they are located close to the waste source. However, a potential for groundwater and soil pollution exists. This issue was discussed by a Group of Experts on Opencast Mining of the UN Economic Commission for Europe because most of the sites are operated by mining companies. This paper contains the major topics of discussion including the significance of the problem, legal aspects, characteristics of the open pits, waste intended for disposal, investigations required to obtain a disposal permit, disposal techniques, protection measures, monitoring environmental impacts, and research trends. A few countries are used as examples

  13. MONITORING OF MINING

    Directory of Open Access Journals (Sweden)

    Berislav Šebečić

    1996-12-01

    Full Text Available The way mining was monitored in the past depended on knowledge, interest and the existing legal regulations. Documentary evidence about this work can be found in archives, libraries and museums. In particular, there is the rich archival material (papers and books concerning the work of the one-time Imperial and Royal Mining Captaincies in Zagreb, Zadar, Klagenfurt and Split, A minor part of the documentation has not yet been transferred to Croatia. From mining handbooks and books we can also find out about mining in Croatia. In the context of Austro-Hungary. For example, we can find out that the first governorships in Zagreb and Zadar headed the Ban, Count Jelacic and Baron Mamula were also the top mining authorities, though this, probably from political motives, was suppressed in the guides and inventories or the Mining Captaincies. At the end of the 1850s, Croatia produced 92-94% of sea salt, up to 8.5% of sulphur, 19.5% of asphalt and 100% of oil for the Austro-Hungarian empire. From data about mining in the Split Mining Captaincy, prepared for the Philadephia Exhibition, it can be seen that in the exploratory mining operations in which there were 33,372 independent mines declared in 1925 they were looking mainly for bauxite (60,0%, then dark coal (19,0%, asphalts (10.3% and lignites (62%. In 1931, within the area covered by the same captaincy, of 74 declared mines, only 9 were working. There were five coal mines, three bauxite mines and one for asphalt. I suggest that within state institution, the Mining Captaincy or Authority be renewed, or that a Mining and Geological Authority be set ap, which would lead to the more complete affirmation of Croatian mining (the paper is published in Croatian.

  14. Lignite and tin ores exploration in southern part of Thailand by using nuclear track-etch detectors

    International Nuclear Information System (INIS)

    Chittrakarn, T.; Boonnummar, R.; Pongsuwan, T.; Nuannin, P.; Kaew-On, C.

    1993-01-01

    Both lignite and tin mines in Southern of Thailand are associated with uranium ore. In lignite exploration, Bangpudum Lignite Mine at Krabi Province was chosen for this studied because we know the exact location and deposition of coal seam by using other geophysical technique and also confirm by borehole. The size 1x2 cm 2 of cellulose nitrate CN-85 films were used, each film was stuck at the inner bottom of a softdrink cup. Each cup was put up side down at the bottom of a borehole about 75 cm depth from the earth surface and laid about 10 m apart. All the cups were put in the hole along the line in order to cover about 280 metre in the cross sectional direction long of the known coal seam. After one month, all the film detectors were collected and etched with 6.25N NaOH at 60 o C about 25 minutes long in order to enlarge the latent alpha registration tracks. These alpha particles were emitted from radon gas (Rn-222) which was generated from uranium associated with lignite ore. The registration track density per area of each CN-85 film was studied by optical microscope at 400x magnifications. We found that the track densities of the films have high correlation with the depth of the known coal seam while high and low track densities will correspond to the shallow and deep coal seam respectively. Also, track density was significantly higher than background. A similar manner of experiment was designed for tin ore exploration at Ronpibul district, Nakorn Si Thammarat province. The result is in progress and will present at the conference. (Author)

  15. Differential-thermal analysis of irradiated lignite

    International Nuclear Information System (INIS)

    Chichek, F.; Eyubova, N.

    2006-01-01

    Full text: In this theme our purpose is to explain thermo-differential analysis of lignites irradiated. During experiment Caraman Ermenek (washed), Caraman Ermenek (crude), Nevshehir (crude), Slopi (crude), Trakya Harman (washed) lignite coals were used. Five of five kinds of coal samples with 3mm and 1gr of each sample were obtained. Then they were filled into the Tubes after having dried total 25 samples with 1 gr at 1000 degrees temperature for one hour. Air in the tubes was pumped out and closed. Coal samples in vacuum medium were irradiated by gamma rays of Co60 at 5.5 kGy, 19.2 kGy, 65.7 kGy, 169.6 kGy, 411.2 kGy doses to the normal conditions. Then differential thermal analysis was carried out both in original and the samples irradiated. Argon gas was used to make inert medium in the camera. T=200-8500 degrees temperature was selected. At the experiment done from 1000-1300 degrees temperatures too great endothermic reaction pick was begun to form by being observed thermal changings. At 3000-4200 degrees temperature exothermic reaction picks and at 7000 degrees parallel exothermic reaction picks were observed. Initial endothermic and exothermic reaction picks in five lignite samples were observed like a sharp curve. At the end coal irradiated samples were compared with original coal samples. At the result of experiment it was revealed that in comparison with original coal samples coal samples irradiated form exothermic and endothermic curves at very reaction pick and temperature intervals of these pick were large. Besides loss of weight was observed to begin at low temperatures in samples irradiated and especially momentary weight loss at some heats in the rang of known temperatures was observed in the coal Slopi contain in bitumen. Because of heat the weigh loss in the non irradiated samples forms parabolic curve and because of heat the weight loss in the samples irradiated forms stepped curves. It has shown that the coal irradiated can be easily departed by

  16. Subsidence prediction in Estonia's oil shale mines

    International Nuclear Information System (INIS)

    Pastarus, J.R.; Toomik, A.

    2000-01-01

    This paper analysis the stability of the mining blocks in Estonian oil shale mines, where the room-and-pillar mining system is used. The pillars are arranged in a singular grid. The oil shale bed is embedded at the depth of 40-75 m. The processes in overburden rocks and pillars have caused the subsidence of the ground surface. The conditional thickness and sliding rectangle methods performed calculations. The results are presented by conditional thickness contours. Error does not exceed 4%. Model allows determining the parameters of spontaneous collapse of the pillars and surface subsidence. The surface subsidence parameters will be determined by conventional calculation scheme. Proposed method suits for stability analysis, failure prognosis and monitoring. 8 refs

  17. Adsorption of an anionic dispersant on lignite

    Energy Technology Data Exchange (ETDEWEB)

    Yavuz, R.; Kucukbayrak, S. [Istanbul Technical University, Istanbul (Turkey). Dept. of Chemical Engineering, Chemical & Metallurgical Engineering Faculty

    2001-12-01

    Since coal is not a homogeneous substance but a mixture of carbonaceous materials and mineral matter, it has a variety of surface properties. Therefore, it is not easy to control the properties of coal suspensions by simply adjusting variables, such as pH and/or electrolyte. A chemical agent needs to be added to control the properties of the coal suspensions. The adsorption behavior of an anionic dispersant in the presence of a wetting agent using some Turkish lignite samples was investigated. The effects of dispersant concentration, temperature and pH on the dispersant adsorption were studied systematically, and the experimental results are presented. Pellupur B69 as a dispersant, commercial mixture of formaldehyde condensate sodium salt of naphthalene sulphonic acid, and Texapon N{sub 2}5 as a wetting agent, a sodium lauryl ether sulfate, have been used.

  18. COFIRING BIOMASS WITH LIGNITE COAL; F

    International Nuclear Information System (INIS)

    Darren D. Schmidt

    2001-01-01

    As of September 28, 2001, all the major project tasks have been completed. A presentation was given to the North Dakota State Penitentiary (NDSP) and the North Dakota Division of Community Services (DCS). In general, the feasibility study has resulted in the following conclusions: (1) Municipal wood resources are sufficient to support cofiring at the NDSP. (2) Steps have been taken to address all potential fuel-handling issues with the feed system design, and the design is cost-effective. (3) Fireside issues of cofiring municipal wood with coal are not of significant concern. In general, the addition of wood will improve the baseline performance of lignite coal. (4) The energy production strategy must include cogeneration using steam turbines. (5) Environmental permitting issues are small and do not affect economics. (6) The base-case economic scenario provides for a 15-year payback of a 20-year municipal bond and does not include the broader community benefits that can be realized

  19. Differential-thermal analysis of irradiated lignite

    International Nuclear Information System (INIS)

    Chichek, F; Eyubova, N.

    2006-01-01

    Full text: In this theme our purpose is to explain thermo-differential analysis of lignite's irradiated. During experiment Caraman Ermenek (washed), Caraman Ermenek (crude), Nevshehir (crude), Slopi (crude), Trakya Harman (washed) lignite coals were used. Five of five kinds of coal samples with 3mm and 1 gr of each sample were obtained. Then they were filled into the Tubes after having dried total 25 samples with 1 gr at 1000C temperature for one hour. Air in the tubes was pumped out and closed. Coal samples in vacuum medium were irradiated by gamma rays of Co-60 at 5.5 kGy, 19.2 kGy, 65.7 kGy, 169.6 kGy, 411.2 kGy, doses to the normal conditions. At the end coal irradiated samples were compared with original coal samples. At the result of experiment it was revealed that in comparison with original coal samples coal samples irradiated from exothermic and endothermic curves at very reaction pick and temperature intervals of these pick were large. Besides loss of weight was observed to begin at low temperatures in samples irradiated and especially momentary weight loss at some heats in the rang of known temperatures was observed in the coal Slopi contain in bitumen. Because of heat the weight loss in the non irradiated samples forms parabolic curve and because of heat the weight loss in the samples irradiated forms stepped curves. It was shown that the coal irradiated can be easily departed by heat because of the chemical structure in comparison the original one.

  20. Microstructure and properties of lignite tar and pitch. Part II

    Energy Technology Data Exchange (ETDEWEB)

    Walther, H

    1954-01-01

    Photomicrographs reveal the presence of crystalline wax which affects the working properties in lignite tars and pitch. The crystals are large needles after slow cooling and small after rapid cooling. The crystals are paraffinic in character. All samples were nonhomogeneous. Thus the properties of lignite tar and pitch are varied by the source of the lignite and history of the specimen, neither softening point nor dropping point seems to satisfactorily characterize these tars. The samples exhibit thixotropic behavior characteristic of a structural viscosity and show hysteresis loops on varying the working rate. The variations have hindered use of lignite tars and pitches except where solubility in a solvent such as coal tar oil can be used to advantage.

  1. Preparation and extraction of sloping seams without leaving inter-drift coal pillars

    Energy Technology Data Exchange (ETDEWEB)

    Artamonov, N S; Bormotov, I N; Brovko, I I

    1977-10-01

    A description is given of mining three coal seams in the Kuznetsk Basin without leaving coal pillars because they could not withstand the stress of the induced reference pressure. This system reduced coal losses in 1976 in comparison to 1970 and eliminated local accumulations of methane by withdrawing it through the excavated area. The system was noted to have the disadvantage of additional expenditures for timber supports. 2 figures.

  2. Numerical analysis of single and multiple particles of Belchatow lignite dried in superheated steam

    Science.gov (United States)

    Zakrzewski, Marcin; Sciazko, Anna; Komatsu, Yosuke; Akiyama, Taro; Hashimoto, Akira; Kaneko, Shozo; Kimijima, Shinji; Szmyd, Janusz S.; Kobayashi, Yoshinori

    2018-03-01

    Low production costs have contributed to the important role of lignite in the energy mixes of numerous countries worldwide. High moisture content, though, diminishes the applicability of lignite in power generation. Superheated steam drying is a prospective method of raising the calorific value of this fuel. This study describes the numerical model of superheated steam drying of lignite from the Belchatow mine in Poland in two aspects: single and multi-particle. The experimental investigation preceded the numerical analysis and provided the necessary data for the preparation and verification of the model. Spheres of 2.5 to 30 mm in diameter were exposed to the drying medium at the temperature range of 110 to 170 °C. The drying kinetics were described in the form of moisture content, drying rate and temperature profile curves against time. Basic coal properties, such as density or specific heat, as well as the mechanisms of heat and mass transfer in the particular stages of the process laid the foundations for the model construction. The model illustrated the drying behavior of a single particle in the entire range of steam temperature as well as the sample diameter. Furthermore, the numerical analyses of coal batches containing particles of various sizes were conducted to reflect the operating conditions of the dryer. They were followed by deliberation on the calorific value improvement achieved by drying, in terms of coal ingredients, power plant efficiency and dryer input composition. The initial period of drying was found crucial for upgrading the quality of coal. The accuracy of the model is capable of further improvement regarding the process parameters.

  3. Lignite chemical conversion in an indirect heat rotary kiln gasifier

    Directory of Open Access Journals (Sweden)

    Hatzilyberis Kostas S.

    2006-01-01

    Full Text Available The results on the gasification of Greek lignite using two indirect heat (allothermal pilot rotary kiln gasifiers are reported in the present work. The development of this new reactor-gasifier concept intended for solid fuels chemical conversion exploits data and experience gained from the following two pilot plants. The first unit A (about 100 kg/h raw lignite demonstrated the production of a medium heating value gas (12-13 MJ/Nm3 with quite high DAF (dry ash free coal conversions, in an indirect heat rotary gasifier under mild temperature and pressure conditions. The second unit B is a small pilot size unit (about 10 kg/h raw lignite comprises an electrically heated rotary kiln, is an operation flexible and exhibits effective phase mixing and enhanced heat transfer characteristics. Greek lignite pyrolysis and gasification data were produced from experiments performed with pilot plant B and the results are compared with those of a theoretical model. The model assumes a scheme of three consecutive-partly parallel processes (i. e. drying, pyrolysis, and gasification and predicts DAF lignite conversion and gas composition in relatively good agreement with the pertinent experimental data typical of the rotary kiln gasifier performance. Pilot plant B is currently being employed in lime-enhanced gasification studies aiming at the production of hydrogen enriched synthesis gas. Presented herein are two typical gas compositions obtain from lignite gasification runs in the presence or not of lime. .

  4. Active containment systems incorporating modified pillared clays

    International Nuclear Information System (INIS)

    Lundie, P.; McLeod, N.

    1997-01-01

    The application of treatment technologies in active containment systems provides a more advanced and effective method for the remediation of contaminated sites. These treatment technologies can be applied in permeable reactive walls and/or funnel and gate systems. The application of modified pillared clays in active containment systems provides a mechanism for producing permeable reactive walls with versatile properties. These pillared clays are suitably modified to incorporate reactive intercalatants capable of reacting with both a broad range of organic pollutants of varying molecular size, polarity and reactivity. Heavy metals can be removed from contaminated water by conventional ion-exchange and other reactive processes within the clay structure. Complex contamination problems can be addressed by the application of more than one modified clay on a site specific basis. This paper briefly describes the active containment system and the structure/chemistry of the modified pillared clay technology, illustrating potential applications of the in-situ treatment process for contaminated site remediation

  5. Rockburst Disaster Prediction of Isolated Coal Pillar by Electromagnetic Radiation Based on Frictional Effect

    Science.gov (United States)

    Zhao, Tongbin; Yin, Yanchun; Xiao, Fukun; Tan, Yunliang; Zou, Jianchao

    2014-01-01

    Based on the understanding that charges generated during coal cracking are due to coal particle friction, a microstructure model was developed by considering four different variation laws of friction coefficient. Firstly, the frictional energy release of coal sample during uniaxial compressive tests was investigated and discussed. Then electromagnetic radiation method was used to predict the potential rockburst disaster in isolated coal pillar mining face, Muchengjian Colliery. The results indicate that the friction coefficient of coal particles decreases linearly with the increase of axial loading force. In predicting the strain-type rockburst, the high stress state of coal must be closely monitored. Field monitoring shows that electromagnetic radiation signal became abnormal before the occurrence of rockburst during isolated coal pillar mining. Furthermore, rockburst tends to occur at the early and ending stages of isolated coal pillar extraction. Mine-site investigation shows the occurrence zone of rockburst is consistent with the prediction, proving the reliability of the electromagnetic radiation method to predict strain-type rockburst disaster. PMID:25054186

  6. Rockburst Disaster Prediction of Isolated Coal Pillar by Electromagnetic Radiation Based on Frictional Effect

    Directory of Open Access Journals (Sweden)

    Tongbin Zhao

    2014-01-01

    Full Text Available Based on the understanding that charges generated during coal cracking are due to coal particle friction, a microstructure model was developed by considering four different variation laws of friction coefficient. Firstly, the frictional energy release of coal sample during uniaxial compressive tests was investigated and discussed. Then electromagnetic radiation method was used to predict the potential rockburst disaster in isolated coal pillar mining face, Muchengjian Colliery. The results indicate that the friction coefficient of coal particles decreases linearly with the increase of axial loading force. In predicting the strain-type rockburst, the high stress state of coal must be closely monitored. Field monitoring shows that electromagnetic radiation signal became abnormal before the occurrence of rockburst during isolated coal pillar mining. Furthermore, rockburst tends to occur at the early and ending stages of isolated coal pillar extraction. Mine-site investigation shows the occurrence zone of rockburst is consistent with the prediction, proving the reliability of the electromagnetic radiation method to predict strain-type rockburst disaster.

  7. Water condensation on ultrahydrophobic flexible micro pillar surface

    Science.gov (United States)

    Narhe, Ramchandra

    2016-05-01

    We investigated the growth dynamics of water drops in controlled condensation on ultrahydrophobic geometrically patterned polydimethylsiloxane (PDMS) cylindrical micro pillars. At the beginning, the condensed drops size is comparable to the pattern dimensions. The interesting phenomenon we observe is that, as the condensation progresses, water drops between the pillars become unstable and enforced to grow in the upward direction along the pillars surface. The capillary force of these drops is of the order of μ\\text{N} and acts on neighboring pillars. That results into bending of the pillars. Pillars bending enhances the condensation and favors the most energetically stable Wenzel state.

  8. Scattering of spermatozoa off cylindrical pillars

    Science.gov (United States)

    Bukatin, Anton; Lushi, Enkeleida; Kantsler, Vasily

    2017-11-01

    The motion of micro-swimmers in structured environments, even though crucial in processes such as in vivo and in vitro egg fertilization, is still not completely understood. We combine microfluidic experiments with mathematical modeling of 3D swimming near convex surfaces to quantify the dynamics of individual sperm cells in the proximity of cylindrical pillars. Our results show that the hydrodynamic and contact forces that account for the shape asymmetry and flagellar motion, are crucial in correctly describing the dynamics observed in the experiments. Last, we discuss how the size of the cylindrical obstacles determines whether the swimmers scatter off or get trapped circling the pillar.

  9. Field emission from a single nanomechanical pillar

    International Nuclear Information System (INIS)

    Kim, Hyun S; Qin Hua; Westphall, Michael S; Smith, Lloyd M; Blick, Robert H

    2007-01-01

    We measured field emission from a silicon nanopillar mechanically oscillating between two electrodes. The pillar has a height of about 200 nm and a diameter of 50 nm, allowing resonant mechanical excitations at radio frequencies. The tunnelling barriers for field emission are mechanically modulated via displacement of the gold island on top of the pillar. We present a rich frequency-dependent response of the emission current in the frequency range of 300-400 MHz at room temperature. Modified Fowler-Nordheim field emission is observed and attributed to the mechanical oscillations of the nanopillar

  10. Ground engineering principles and practices for underground coal mining

    CERN Document Server

    Galvin, J M

    2016-01-01

    This book teaches readers ground engineering principles and related mining and risk management practices associated with underground coal mining. It establishes the basic elements of risk management and the fundamental principles of ground behaviour and then applies these to the essential building blocks of any underground coal mining system, comprising excavations, pillars, and interactions between workings. Readers will also learn about types of ground support and reinforcement systems and their operating mechanisms. These elements provide the platform whereby the principles can be applied to mining practice and risk management, directed primarily to bord and pillar mining, pillar extraction, longwall mining, sub-surface and surface subsidence, and operational hazards. The text concludes by presenting the framework of risk-based ground control management systems for achieving safe workplaces and efficient mining operations. In addition, a comprehensive reference list provides additional sources of informati...

  11. Water protection problems in Sachsen mines

    International Nuclear Information System (INIS)

    Schmidt, R.

    2004-01-01

    European regulations must be integrated in national law in order to become valid in its member states. In Germany, the Mining Act was amended in 1990, and an environmental impact statement was introduced in the plan approval procedure. Further, a safety and health certificate was required by the new ordinance on safety in mining (ABBergV). At state level, the German states are still in the modification and integration procedure. In the state of Sachsen, it is intended to give privilege to all mining projects instead of just to lignite mining as in the past. (orig.) [de

  12. Normalising corporate counterinsurgency: Engineering consent, managing resistance and greening destruction around the Hambach coal mine and beyond

    NARCIS (Netherlands)

    Dunlap, A.A.

    2018-01-01

    The German Rhineland is home to the world's largest opencast lignite coal mine and human-made hole – the Hambach mine. Over the last seven years, RWE, the mine operator, has faced an increase in militant resistance, culminating in the occupation of the Hambacher Forest and acts of civil disobedience

  13. Preliminary creep and pillar closure data for shales

    International Nuclear Information System (INIS)

    Lomenick, T.F.; Russell, J.E.

    1987-10-01

    The results of fourteen laboratory creep tests on model pillars of four different shales are reported. Initial pillar stresses range from 6.9 MPa (1000 psi) to 69 MPa (10,000 psi) and temperatures range from ambient to 100 0 C. Laboratory response data are used to evaluate the parameters in the transient power-law pillar closure equation similar to that previously used for model pillars of rock salt. The response of the model pillars of shale shows many of the same characteristics as for rock salt. Deformation is enhanced by higher stresses and temperatures, although the shale pillars are not as sensitive to either stress or temperature as are pillars of rock salt. These test results must be considered very preliminary since they represent the initial, or scoping, phase of a comprehensive model pillar test program that will lead to the development and validation of creep laws for clay-rich rocks. 11 refs., 9 figs., 7 tabs

  14. Empirical pillar design methods review report: Final report

    International Nuclear Information System (INIS)

    1988-02-01

    This report summarizes and evaluates empirical pillar design methods that may be of use during the conceptual design of a high-level nuclear waste repository in salt. The methods are discussed according to category (i.e, main, submain, and panel pillars; barrier pillars; and shaft pillars). Of the 21 identified for main, submain, and panel pillars, one method, the Confined Core Method, is evaluated as being most appropriate for conceptual design. Five methods are considered potentially applicable. Of six methods identified for barrier pillars, one method based on the Load Transfer Distance concept is considered most appropriate for design. Based on the evaluation of 25 methods identified for shaft pillars, an approximate sizing criterion is proposed for use in conceptual design. Aspects of pillar performance relating to creep, ground deformation, interaction with roof and floor rock, and response to high temperature environments are not adequately addressed by existing empirical design methods. 152 refs., 22 figs., 14 tabs

  15. Structural insights from boron tribromide ether cleavage into lignites and low maturity coals from the New Zealand Coal Band

    DEFF Research Database (Denmark)

    Glombitza, Clemens; Mangelsdorf, Kai; Horsfield, Brian

    2011-01-01

    structure, boron tribromide (BBr3) ether cleavage was applied to a series of lignite and coal samples of different maturity (R0 0.27–0.80%) obtained from coal mines and natural outcrops from the North and South Island of New Zealand. Terminal ether-bound alcohols rapidly decrease during diagenesis and occur...... over geological time scales. Polyether compounds were detected with chain length up to five carbon atoms. After a small decrease during the diagenetic phase these compounds occur in relatively high concentrations, even in the main catagenetic stage. This suggests that these linkage structures represent...

  16. Measurements of very large deformations in potash salt in conjunction with an ongoing mining operation

    International Nuclear Information System (INIS)

    Sattler, A.R.; Christensen, C.L.

    1980-01-01

    Room and pillar deformation were measured in conjunction with a relatively new type of mining operation in a southeastern New Mexico potash mine. The extraction ration was approximately 90 percent in a first mining operation. Due to severe deformations encountered, instrumentation had to be developed/modified for these measurements. This paper concentrates on experiment design, design of special instrumentation, field installation of equipment, and presentation of the data. Measurements made include extensometers in the pillar, in the floor and ceiling in the room between pillars, absolute level measurements, floor ceiling closure, and stress (strain) measurements. Associated laboratory rock mechanics measurements of samples from the mine are being done separately. Two separate room pillar complexes were instrumented. In the first complex, floor-ceiling deformations of approximately 1 inch/day and pillar deformations around 1/2 inch/day were measured. In the second complex, instrumentation was installed while the pillar was a part of a long wall and the subsequent sequential mining (long wall-pillar with only one adjoining room on one side - pillar in the middle of room pillar complex) was observed. Data return from this operation was good

  17. Use of INAA for investigation of emission of elements in combustion of Polish lignite

    International Nuclear Information System (INIS)

    Janczyszyn, J.; Loska, L.; Pohorecki, W.; Wagner, M.

    2002-01-01

    Instrumental neutron activation analysis (INAA) has been applied for the determination of trace elements content in samples of Polish lignite and its ash. Pairs of results, for lignite and ash, and respective ash contents were used for calculation of the percentage of element remaining in ash after the lignite combustion. (author)

  18. Methane layering in bord and pillar workings.

    CSIR Research Space (South Africa)

    Creedy, DP

    1997-08-01

    Full Text Available This report reviews the state of knowledge on the occurrence, investigation, detection, monitoring, prevention and dispensation of methane layers in coal mines. Mining practice throughout the world in respect of methane layering is generally reliant...

  19. Effects of pillar height and junction depth on the performance of radially doped silicon pillar arrays for solar energy applications

    NARCIS (Netherlands)

    Elbersen, R.; Vijselaar, Wouter Jan, Cornelis; Tiggelaar, Roald M.; Gardeniers, Johannes G.E.; Huskens, Jurriaan

    2016-01-01

    The effects of pillar height and junction depth on solar cell characteristics are investigated to provide design rules for arrays of such pillars in solar energy applications. Radially doped silicon pillar arrays are fabricated by deep reactive ion etching of silicon substrates followed by the

  20. Influence of a Large Pillar on the Optimum Roadway Position in an Extremely Close Coal Seam

    Directory of Open Access Journals (Sweden)

    Li Yang

    2016-01-01

    Full Text Available Based on the mining practice in an extremely close coal seam, theoretical analysis was conducted on the vertical stress distribution of the floor strata under a large coal pillar. The vertical stress distribution regulation of a No. 5 coal seam was revealed. To obtain the optimum position of the roadway that bears the supporting pressure of a large coal pillar, numerical modeling was applied to analyze the relation among the stress distribution of the roadway surrounding the rock that bears the supporting pressure of a large coal pillar, the plastic zone distribution of the roadway surrounding the rock, the surrounding rock deformation, and the roadway layout position. The theoretical calculation results of the stress value, stress variation rate, and influencing range of the stress influencing angle showed that the reasonable malposition of the No. 5 coal seam roadway was an inner malposition of 4 m. The mining practice showed the following: the layout of No. 25301 panel belt roadway at the position of the inner malposition of 4 m was reasonable, the roadway support performance was favourable without deformation, and ground pressure was not obvious. The research achievement of this study is the provision of a reference for roadway layouts under similar conditions.

  1. Natural desulfurization in coal-fired units using Greek lignite.

    Science.gov (United States)

    Konidaris, Dimitrios N

    2010-10-01

    This paper analyzes the natural desulfurization process taking place in coal-fired units using Greek lignite. The dry scrubbing capability of Greek lignite appears to be extremely high under special conditions, which can make it possible for the units to operate within the legislative limits of sulfur dioxide (SO2) emissions. According to this study on several lignite-fired power stations in northern Greece, it was found that sulfur oxide emissions depend on coal rank, sulfur content, and calorific value. On the other hand, SO2 emission is inversely proportional to the parameter gammaCO2(max), which is equal to the maximum carbon dioxide (CO2) content by volume of dry flue gas under stoichiometric combustion. The desulfurization efficiency is positively correlated to the molar ratio of decomposed calcium carbonate to sulfur and negatively correlated to the free calcium oxide content of fly ash.

  2. Transformation of heavy metals in lignite during supercritical water gasification

    International Nuclear Information System (INIS)

    Chen, Guifang; Yang, Xinfei; Chen, Shouyan; Dong, Yong; Cui, Lin; Zhang, Yong; Wang, Peng; Zhao, Xiqiang; Ma, Chunyuan

    2017-01-01

    Highlights: • The transformations of heavy metals during lignite SCWG were investigated. • The risks of heavy metals in lignite and residues after SCWG were evaluated. • The effects of experimental conditions on corrosion during SCWG were studied. - Abstract: Transformation characteristics of heavy metals during lignite supercritical water gasification (SCWG) were studied. A sequential extraction procedure (modified Tessier method) was used to selectively extract different fractions of Pb, Cd, Cr, Mn, Cu, Ni, and Zn. Heavy metals transformed into more stable fractions after SCWG. For Pb, Cd, Mn, Cu, and Zn, SCWG reduced the bioavailability and the risks posed by heavy metals in lignite. Under the experimental conditions, the conversion rates for Pb and Cd were 16.0%–25.2% and 16.3%–23.4%, respectively, whereas those for Mn, Cu, and Zn were much lower. Solid products enriched with Pb, Cd, Mn, Cu, and Zn were obtained after SCWG; the contents of these metals varied slightly in the liquid products under different experimental conditions. Excess Cr and Ni that did not originate from lignite were found in the residues, owing to reactor corrosion during lignite SCWG. Higher temperatures alleviated corrosion, whereas higher pressures and equivalence ratios (ER) had the opposite effect. None of the heavy metals were detected in the gas phase under the experimental conditions used in the present study. The correlation between the distributions of heavy metals and the experimental conditions were also studied. The transformation pathways of Pb, Cd, Mn, Cu, and Zn during SCWG were deduced according to the experimental results.

  3. The Evaluation Of Waste Plastic Burned With Lignite And Biomass

    OpenAIRE

    DURANAY, Neslihan; YILGIN, Melek

    2016-01-01

    In this work, the combustion behavior of pellets prepared from binary and triple blends of waste plastic, biomass and lignite was investigated in an experimental fixed bed combustion system. Market bags as plastic waste and the furniture factory waste powder as a source of biomass and Bingöl Karlıova coal as a lignite were used. The effect of process temperature and the plastic mixing ratio on the combustion behavior of pellets was studied. Combustion data obtained from varied bed temperature...

  4. Extending and implementing the Persistent ID pillars

    Science.gov (United States)

    Car, Nicholas; Golodoniuc, Pavel; Klump, Jens

    2017-04-01

    The recent double decade anniversary of scholarly persistent identifier use has triggered journal special editions such as "20 Years of Persistent Identifiers". For such a publication, it is apt to consider the longevity of some persistent identifier (PID) mechanisms (Digital Object Identifiers) and the partial disappearance of others (Life Sciences IDs). We have previously postulated a set of "PID Pillars" [1] which are design principles aimed at ensuring PIDs can survive technology and social change and thus persist for the long term that we have drawn from our observations of PIDs at work over many years. The principles: describe how to ensure identifiers' system and organisation independence; codify the delivery of essential PID system functions; mandate a separation of PID functions from data delivery mechanisms; and require generation of policies detailing how change is handled. In this presentation, first we extend on our previous work of introducing the pillars by refining their descriptions, giving specific suggestions for each and presenting some work that addresses them. Second, we propose a baseline data model for persistent identifiers that, if used, would assist the separation of PID metadata and PID system functioning. This would allow PID system function specifics to change over time (e.g. resolver services or even resolution protocols) and yet preserve the PIDs themselves. Third, we detail our existing PID system — the PID Service [2] — that partially implements the pillars and describe both its successes and shortcomings. Finally, we describe our planned next-generation system that will aim to use the baseline data model and fully implement the pillars.

  5. Mining Method

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Shik; Lee, Kyung Woon; Kim, Oak Hwan; Kim, Dae Kyung [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1996-12-01

    The reducing coal market has been enforcing the coal industry to make exceptional rationalization and restructuring efforts since the end of the eighties. To the competition from crude oil and natural gas has been added the growing pressure from rising wages and rising production cost as the workings get deeper. To improve the competitive position of the coal mines against oil and gas through cost reduction, studies to improve mining system have been carried out. To find fields requiring improvements most, the technologies using in Tae Bak Colliery which was selected one of long running mines were investigated and analyzed. The mining method appeared the field needing improvements most to reduce the production cost. The present method, so-called inseam roadway caving method presently is using to extract the steep and thick seam. However, this method has several drawbacks. To solve the problems, two mining methods are suggested for a long term and short term method respectively. Inseam roadway caving method with long-hole blasting method is a variety of the present inseam roadway caving method modified by replacing timber sets with steel arch sets and the shovel loaders with chain conveyors. And long hole blasting is introduced to promote caving. And pillar caving method with chock supports method uses chock supports setting in the cross-cut from the hanging wall to the footwall. Two single chain conveyors are needed. One is installed in front of chock supports to clear coal from the cutting face. The other is installed behind the supports to transport caved coal from behind. This method is superior to the previous one in terms of safety from water-inrushes, production rate and productivity. The only drawback is that it needs more investment. (author). 14 tabs., 34 figs.

  6. The role of the nature of pillars in the structural and magnetic properties of magnetic pillared vlays

    DEFF Research Database (Denmark)

    Bachir, Cherifa; Lan, Yanhua; Mereacre, Valeriu

    2011-01-01

    of pillared clays by examining in detail the influence of the calcination temperature and the nature of different pillared clays on these properties. Magnetic layered systems from different pillared clays were prepared and characterized. Firstly, Ti-, Al-, and Zr-pillared clays (Ti-PILCs, Al-PILCs, and Zr......-PILCs, respectively) were produced at different calcination temperatures and then magnetic pillared clays (Ti-M-PILCs, Al-M-PILCs, and Zr-M-PILCs) were prepared at ambient temperature. The synthesis involves a reduction in aqueous solution of the original Fe-exchanged pillared clay using NaBH4. The structural....... Similar experiments with Al- and Zr-pillars have been discussed. A correlation between the XRF data, porosity, FF calculation, and magnetic properties led to the conclusion that the sample Al-M-PILC previously calcined at 500 degrees C was the most stable material after the magnetization process. The same...

  7. Mine for sale

    International Nuclear Information System (INIS)

    Beer, G.

    2006-01-01

    The newest Slovak brown coal mine - Bana Zahorie is in crisis. Despite the fact that experts believe that along with Bana Novaky, it has the most potential. The owners have started its liquidation. One of the walls has collapsed and another part flooded. Nobody was hurt, but some equipment is still underground. The mine had already lost equipment in the past. During an accident in 2000, equipment worth several tens of millions was destroyed. 'After the accident, mining had to be stopped and from a technical point of view that was the end of the joint stock company, Bana Zahorie Cary. The company could not raise the funds necessary to recover from the accident,' stated the Director of the mine, Jan Palkovic. But he stressed that only the joint stock company is in liquidation, the mine is still being ventilated and the water is being pumped out. But the company management still does not want to specify who will become the new owner of the lignite deposits in Zahorie. The Director promised to publish more details within several weeks. All competencies and mining rights of the former Bana Zahorie are being transferred to a new company - joint stock company Bana Cary. (author)

  8. The relation between district raise in the multiple coal seams and its pillars

    Energy Technology Data Exchange (ETDEWEB)

    Zhai, X. [Jiaozuo Institute of Technology, Jiaozuo (China). Dept. of Mining Engineering

    2002-02-01

    Based on the geological condition of multiple coal seams mining in No.8 Colliery of Pingdingshan Coal Group, the behaviours of the front abutment pressure in each of the coal seams and the fixed abutment pressure are observed. The main cause of deformation and damage to the galleries is the increasing value of the valid load coefficient of the surrounding rock. The rational pillar width of the district raise is studied when its two side seams have been mined, and the layout question of district raise in the different set of seams is also studied. The conclusions derived from the study are useful guiding reference for the design of district raise layout in deep multiple coal seams mining. 6 refs., 3 figs., 1 tab.

  9. Coal mining in Spain: first half year 1986

    Energy Technology Data Exchange (ETDEWEB)

    1986-01-01

    Statistical data from the first half of 1986 on coal mining in Spain. These figures cover anthracite, bituminous coal and lignite both nationally and for the coal-producing regions of Leon, Asturias, Palencia, Teruel and La Coruna. Special attention is paid to absenteeism and its causes.

  10. The mine planning process for an open-pit diamond mining operation - a case study on Letseng diamond mine in Lesotho

    OpenAIRE

    Madowe, A.

    2013-01-01

    This paper discusses the mine planning process for Letseng diamond mine in the Kingdom of Lesotho, in conjunction with the various software packages used during the process. The major pillars of the long-term mine planning process at Letseng are pit optimization followed by pit design and scheduling. Letseng uses Gemcom Whittle and GEMS for pit optimization and design and Runge XPAC for scheduling. The output of the mine planning process results in the generation of published mineral reserves...

  11. Determination of ash-forming elements in lignite coal

    International Nuclear Information System (INIS)

    Wischnewski, C.; Werner, G.; Vogt, J.; Just, G.

    1990-01-01

    The most important methods are discussed suitable for the determination of ash-forming elements in coal. In this connection questions of the concentrations of elements in lignites, of the sample preparation, and of the selection of methods for the determination of ash-forming elements are addressed. Advantages and disadvantages of different analysis techniques are shown using concrete examples. (author)

  12. Mineralogy and geochemistry of density-separated Greek lignite fractions

    NARCIS (Netherlands)

    Iordanidis, A.; Doesburg, van J.D.J.

    2006-01-01

    In this study, lignite samples were collected from the Ptolemais region, northern Greece, homogenized, crushed to less than I nun, and separated in three density fractions using heavy media. The mineralogical investigation of the density fractions showed a predominance of pyrite in the light

  13. Pyrolysis kinetics of phenols from lignite semicoking tar

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Polovetskaya, O.S.; Proskuryakov, V.A.; Shavyrina, O.A. [Leo Tolstoy Tula State Pedag University, Tula (Russian Federation)

    2002-11-01

    The features of pyrolysis of phenols from lignite semicoking tar were studied. The activation energy and order of the reactions of accumulation of methane, hydrogen, carbon monoxide and dioxide, naphthalene and its methyl homologs, phenols, and isomeric cresols and dimethylphenols were determined.

  14. Cheap carbon sorbents produced from lignite by catalytic pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, B.N.; Schchipko, M.L. [Inst. of Chemistry of Natural Organic Materials, Akademgorodok, Krasnoyarsk (Russian Federation)

    1995-12-01

    Some data are presented describing the new technology of carbon sorbent production from powdered lignite in the installation with fluidized bed of catalyst. It was shown the different types of char products with extended pore structure and high sorption ability can be produced from cheap and accessible lignite of Kansk-Achinsk coal pit in pilot installation with fluidized bed of Al-Cu-Cr oxide catalyst or catalytically active slag materials. In comparison with the conventional technologies of pyrolysis the catalytic pyrolysis allows to increase by 3-5 times the process productivity and to decrease significantly the formation of harmful compounds. The latter is accomplished by complete oxidation of gaseous pyrolysis products in the presence of catalysts and by avoiding the formation of pyrolysis tars - the source of cancerogenic compounds. The technology of cheap powdered sorbent production from lignites makes possible to obtain from lignite during the time of pyrolysis only a few seconds char products with porosity up to 0.6 cm{sup 3} /g, and specific surface area more than 400 m{sup 3} /g. Some methods of powdered chars molding into carbon materials with the different shape were proved for producing of firmness sorbents. Cheap carbon sorbents obtained by thermocatalytic pyrolysis can be successfully used in purification of different industrial pollutants as one-time sorbent or as adsorbents of long-term application with periodic regeneration.

  15. Trigeneration integrated with absorption enhanced reforming of lignite and biomass

    Energy Technology Data Exchange (ETDEWEB)

    Yaodong Wang; Ye Huang; Anthony P. Roskilly [Newcastle University, Newcastle Upon Tyne (United Kingdom). Sir Joseph Swan Institute for Energy Research

    2009-10-15

    A technical investigation of an innovative trigeneration integrated with absorption enhanced reforming (AER) of lignite and biomass is carried out using the ECLIPSE process simulator. The system includes an internal combustion engine, an AER gasifier, a waste heat recovery and storage unit and an absorption refrigerator. The whole system is operated in the following sequence: The AER gasifier is used to generate hydrogen using lignite and biomass; the hydrogen generated is used to run the engine which drives a generator to produce electricity. Additionally, the heat recovery unit collects waste heat from the engine and is used to supply hot water and space heating. Furthermore, the waste heat is used to operate the absorption refrigerator. The electricity, heat and cooling can be used to meet the energy requirements for the households in a village, a resident building or a commercial building, or a supermarket. Within the study, the effects of lignite mixed with three different types of biomass (straw, willow and switch grass) on the system performance are investigated and the results are compared. The results show that it is feasible to use an AER system to reform the low quality fuels lignite and biomass to generate a cleaner fuel - hydrogen to replace fossil fuels (diesel or natural gas) and to fuel an engine based trigeneration system; the system works with high efficiencies and with a potential of carbon capture from the sorbent-regeneration process that would benefit the environment. 25 refs., 2 figs., 3 tabs.

  16. Catalytic Wastewater Treatment Using Pillared Clays

    Science.gov (United States)

    Perathoner, Siglinda; Centi, Gabriele

    After introduction on the use of solid catalysts in wastewater treatment technologies, particularly advanced oxidation processes (AOPs), this review discussed the use of pillared clay (PILC) materials in three applications: (i) wet air catalytic oxidation (WACO), (ii) wet hydrogen peroxide catalytic oxidation (WHPCO) on Cu-PILC and Fe-PILC, and (iii) behavior of Ti-PILC and Fe-PILC in the photocatalytic or photo-Fenton conversion of pollutants. Literature data are critically analyzed to evidence the main direction to further investigate, in particularly with reference to the possible practical application of these technologies to treat industrial, municipal, or agro-food production wastewater.

  17. Quality factors of nonideal micro pillars

    DEFF Research Database (Denmark)

    Gregersen, Niels; Nielsen, Torben Roland; Tromborg, Bjarne

    2007-01-01

    The influence of fabrication-induced imperfections and material absorption on the quality (Q) factor of a microcavity pillar is studied numerically. The dependence on sidewall inclination, selective underetch, and intrinsic loss is quantified. The authors show that imperfections can lead to an im...... to an improvement in Q and that a sidewall inclination angle of less than 1° causes a dramatic change in the Q factor. The variations in Q can be attributed to a delicate balance between effective index contrasts, mode overlap, and higher-order mode contributions....

  18. Surface mining and land reclamation in Germany

    Energy Technology Data Exchange (ETDEWEB)

    Nephew, E.A.

    1972-05-01

    Mining and land restoration methods as well as planning and regulatory procedures employed in West Germany to ameliorate environmental impacts from large-scale surface mining are described. The Rhineland coalfield in North Rhine Westphalia contains some 55 billion tons of brown-coal (or lignite), making the region one of Europe's most important energy centers. The lignite is extracted from huge, open-pit mines, resulting in large areas of disturbed land. The German reclamation approach is characterized by planning and carrying out the mining process as one continuum from early planning to final restoration of land and its succeeding use. Since the coalfield is located in a populated region with settlements dating back to Roman times, whole villages lying in the path of the mining operations sometimes have to be evacuated and relocated. Even before mining begins, detailed concepts must be worked out for the new landscape which will follow: the topography, the water drainage system, lakes and forests, and the intended land-use pattern are designed and specified in advance. Early, detailed planning makes it possible to coordinate mining and concurrent land reclamation activities. The comprehensive approach permits treating the overall problem as a whole rather than dealing with its separate aspects on a piecemeal basis.

  19. Third symposium on underground mining

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-01-01

    The Third Symposium on Underground Mining was held at the Kentucky Fair and Exposition Center, Louisville, KY, October 18--20, 1977. Thirty-one papers have been entered individually into EDB and ERA. The topics covered include mining system (longwall, shortwall, room and pillar, etc.), mining equipment (continuous miners, longwall equipment, supports, roof bolters, shaft excavation equipment, monitoring and control systems. Maintenance and rebuilding facilities, lighting systems, etc.), ventilation, noise abatement, economics, accidents (cost), dust control and on-line computer systems. (LTN)

  20. 10th international conference on ground control in mining - proceedings

    International Nuclear Information System (INIS)

    Peng, S.S.

    1991-01-01

    36 papers are presented covering topics that include longwall pillar design, assessment of underground structural design, load and convergence measurements in longwall faces, shield strata interaction, longwall shield recovery, roof control in longwall mining, anchor resin system, thrust bolting, roof bolts, cable slings, roof support in retreat mining, coal bump prediction, delineation of abandoned workings, stability of coal mine openings, mining under rivers, rock strength determination, subsidence prediction and measurement, drag picks, measuring roof convergence, and finite element modelling of subsidence

  1. Organic petrographical, mineralogical and geochemical features of the Achlada and Mavropigi lignite deposits, NW Macedonia, Greece

    Energy Technology Data Exchange (ETDEWEB)

    Koukouzas, Nikolaos [Centre for Research and Technology Hellas, Institute for Solid Fuels Technology and Applications, Mesogeion Ave. 357-359, GR-15231 Halandri, Athens (Greece); Kalaitzidis, Stavros P. [Geological Services, BHP Billiton Mitsubishi Alliance, Central Queensland Office, Peak Downs Mine, Moranbah, QLD 4744 (Australia); Ward, Colin R. [School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052 (Australia)

    2010-09-01

    The Achlada and Mavropigi lignite deposits in northern Greece provide the main coal source for the next generation of Greek power plants. A comparative characterization of these two lignite deposits is presented, covering the coal rank and the features of the maceral components, based on detailed coal petrography, and the mineralogical and geochemical features of the coals and their ashes, based on XRF and XRD analyses. The data are used to interpret the palaeoenvironments of the lignite beds, as well as factors that may affect their burnout behavior. Both deposits have a lignite C rank. The Mavropigi lignite is mainly a matrix lignite lithotype, whereas the Achlada deposit consists both of matrix and xylite-rich lithotypes. The Achlada lignite was formed in a fluviatile environment, mainly in the abandoned channels of a meandering river system during flooding periods; hence it is enriched in inorganic matter, with ash values > 30 wt.%. The Mavropigi lignite formed in a reed-marsh environment under limno-telmatic conditions, and displays ash values < 30 wt.%. The inorganic matter of the two deposits is different in composition due to the contrasting environments, and these differences should be taken into account in optimizing their utilization for power production. A preliminary assessment indicates that the Achlada lignite may have more favorable slagging and fouling properties than the Mavropigi lignite, although experimental studies are required for more solid conclusions to be reached. (author)

  2. Supercapacitors based on pillared graphene nanostructures.

    Science.gov (United States)

    Lin, Jian; Zhong, Jiebin; Bao, Duoduo; Reiber-Kyle, Jennifer; Wang, Wei; Vullev, Valentine; Ozkan, Mihrimah; Ozkan, Cengiz S

    2012-03-01

    We describe the fabrication of highly conductive and large-area three dimensional pillared graphene nanostructure (PGN) films from assembly of vertically aligned CNT pillars on flexible copper foils for applications in electric double layer capacitors (EDLC). The PGN films synthesized via a one-step chemical vapor deposition process on flexible copper foils exhibit high conductivity with sheet resistance as low as 1.6 ohms per square and possessing high mechanical flexibility. Raman spectroscopy indicates the presence of multi walled carbon nanotubes (MWCNT) and their morphology can be controlled by the growth conditions. It was discovered that nitric acid treatment can significantly increase the specific capacitance of the devices. EDLC devices based on PGN electrodes (surface area of 565 m2/g) demonstrate enhanced performance with specific capacitance value as high as 330 F/g extracted from the current density-voltage (CV) measurements and energy density value of 45.8 Wh/kg. The hybrid graphene-CNT nanostructures are attractive for applications including supercapacitors, fuel cells and batteries.

  3. Bio-solubilization of Chinese lignite II: extra-cellular protein analysis

    Energy Technology Data Exchange (ETDEWEB)

    Tao, Xiu-xiang; Pan, Lan-ying; Shi, Kai-yi; Chen-hui; Yin, Su-dong; Luo, Zhen-fu [China University of Mining & Technology, Xuzhou (China). School of Chemical Engineering and Technology

    2009-05-15

    A white rot fungus strain, Trichoderma sp. AH, was isolated from rotten wood in Fushun and used to study the mechanism of lignite bio-solubilization. The results showed that nitric acid pretreated Fushun lignite was solubilized by T. sp. AH and that extracellular proteins from T. sp. AH were correlated with the lignite bio-solubilization results. In the presence of Fushun lignite the extracellular protein concentration from T. sp. AH was 4.5 g/L while the concentration was 3 g/L in the absence of Fushun lignite. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of the extracelular proteins detected at least four new protein bands after the T. sp. AH had solubilized the lignite. Enzyme color reactions showed that extracelular proteins from T. sp. AH mainly consisted of phenol-oxidases, but that lignin decomposition enzymes such as laccase, peroxidase and manganese peroxidases were not present. 9 refs., 8 figs.

  4. Refining of Macedonian lignite through briquets production

    International Nuclear Information System (INIS)

    Dimitrov, Konstantin; Kachurkov, Gjorgji; Popovski, Kiril; Armenski, Slave

    1998-01-01

    In 1997 for the first time the scientific institutes from Republic of Macedonia got the opportunity to take part in competition to realize the scientific-research activity, financed by European Union. In the area of energy it could be applied for programs TERMI and COPERNICUS. A research project is applied for the program INCO COPERNICUS 97, with participation of the following research institutes: Koppern Aufbereitungstechnik GMbH and Co.KG - Germany; ENTEGRO - Greek Company for Energy Technology - Greece; Mining Institute Skopje - Macedonia; Faculty of Mechanical Engineering, Skopje - Macedonia; Faculty of Technical Sciences, Bitola - Macedonia; Central Institute for work protection, Skopje - Macedonia; Faculty for Industrial Chemistry and Metallurgy - Bulgaria. This paper presents the aim of the research, expected results, methodology and distribution of work among the research institutes

  5. Atmospheric Fluidized Bed Combustion testing of North Dakota lignite

    Energy Technology Data Exchange (ETDEWEB)

    Goblirsch, G; Vander Molen, R H; Wilson, K; Hajicek, D

    1980-05-01

    The sulfur retention by the inherent alkali, and added limestone sorbent, perform about the same and are reasonably predictable within a range of about +-10% retention by application of alkali to sulfur ratio. Temperature has a substantial effect on the retention of sulfur by the inherent alkali or limestone. The temperature effect is not yet fully understood but it appears to be different for different coals and operational conditions. The emission of SO/sub 2/ from the fluid bed burning the Beulah lignite sample used for these tests can be controlled to meet or better the current emission standards. The injection of limestone to an alkali-to-sulfur molar ratio of 1.5 to 1, should lower the SO/sub 2/ emissions below the current requirement of 0.6 lb SO/sub 2//10/sup 6/ Btu to 0.4 lb SO/sub 2//10/sup 6/ Btu, a safe 33% below the standard. Agglomeration of bed material, and consequent loss of fluidization quality can be a problem when burning high sodium lignite in a silica bed. There appears, however, to be several ways of controlling the problem including the injection of calcium compounds, and careful control of operating conditions. The heat transfer coefficients measured in the CPC and GFETC tests are comparable to data obtained by other researchers, and agree reasonably well with empirical conditions. The NO/sub x/ emissions measured in all of the tests on Beulah lignite are below the current New Source Performance Standard of 0.5 lb NO/sub 2//10/sup 6/ Btu input. Combustion efficiencies for the Beulah lignite are generally quite high when ash recycle is being used. Efficiencies in the range of 98% to 99%+ have been measured in all tests using this fuel.

  6. Sorption of heavy metals on lignite impregnated with chitosan

    Czech Academy of Sciences Publication Activity Database

    Havelcová, Martina; Mizera, Jiří; Machovič, V.; Borecká, Lenka; Přibyl, Oldřich; Krausová, Ivana

    2013-01-01

    Roč. 10, č. 1 (2013), s. 105-110 ISSN 1214-9705 R&D Projects: GA ČR(CZ) GBP108/12/G108 Institutional support: RVO:67985891 ; RVO:61389005 Keywords : lignite * chitosan * heavy metals * sorption Subject RIV: DJ - Water Pollution ; Quality Impact factor: 0.667, year: 2013 http://www.irsm.cas.cz/index_en.php?page=acta_detail_doi&id=19

  7. Periodically structured Si pillars for high-performing heterojunction photodetectors

    Science.gov (United States)

    Melvin David Kumar, M.; Yun, Ju-Hyung; Kim, Joondong

    2015-03-01

    A periodical array of silicon (Si) micro pillar structures was fabricated on Si substrates using PR etching process. Indium tin oxide (ITO) layer of 80 nm thickness was deposited over patterned Si substrates so as to make ITO/n-Si heterojunction devices. The influences of width and period of pillars on the optical and electrical properties of prepared devices were investigated. The surface morphology of the Si substrates revealed the uniform array of pillar structures. The 5/10 (width/period) Si pillar pattern reduced the optical reflectance to 6.5% from 17% which is of 5/7 pillar pattern. The current rectifying ratio was found higher for the device in which the pillars are situated in optimum periods. At both visible (600 nm) and near infrared (900 nm) range of wavelengths, the 5/7 and 5/10 pillar patterned device exhibited the better photoresponses which are suitable for making advanced photodetectors. This highly transmittance and photoresponsive pillar patterned Si substrates with an ITO layer would be a promising device for various photoelectric applications.

  8. The catalytic cracking mechanism of lignite pyrolysis char on tar

    International Nuclear Information System (INIS)

    Lei, Z.; Huibin, H.; Xiangling, S.; Zhenhua, M.; Lei, Z.

    2017-01-01

    The influence of different pyrolysis conditions for tar catalytic cracking will be analyzed according to the lignite pyrolysis char as catalyst on pyrolytic tar in this paper. The pyrolysis char what is the by-product of the cracking of coal has an abundant of pore structure and it has good catalytic activity. On this basis, making the modified catalyst when the pyrolysis char is activation and loads Fe by impregnation method. The cracking mechanism of lignite pyrolytic tar is explored by applying gas chromatograph to analyze splitting products of tar. The experimental results showed that: (1) The effect of tar cracking as the pyrolysis temperature, the heating rate, the volatilization of pyrolysis char and particle size increasing is better and better. The effect of the catalytic and cracking of lignite pyrolysis char in tar is best when the heating rate, the pyrolysis temperature, the volatiles of pyrolysis char, particle size is in specific conditions.(2) The activation of pyrolysis char can improve the catalytic effect of pyrolysis char on the tar cracking. But it reduces the effect of the tar cracking when the pyrolysis char is activation loading Fe. (author)

  9. NOx and SO2 emission factors for Serbian lignite Kolubara

    Directory of Open Access Journals (Sweden)

    Jovanović Vladimir V.

    2012-01-01

    Full Text Available Emission factors are widely accepted tool for estimation of various pollutants emissions in USA and EU. Validity of emission factors is strongly related to experimental data on which they are based. This paper is a result of an effort to establish reliable NOx and SO2 emission factors for Serbian coals. The results of NOx and SO2 emissions estimations based on USA and EU emission factors from thermal power plants Nikola Tesla Obrenovac A and B utilizing the Serbian lignite Kolubara are compared with experimental data obtained during almost one decade (2000-2008 of emissions measurements. Experimental data are provided from regular annual emissions measurement along with operational parameters of the boiler and coal (lignite Kolubara ultimate and proximate analysis. Significant deviations of estimated from experimental data were observed for NOx, while the results for SO2 were satisfactory. Afterwards, the estimated and experimental data were plotted and linear regression between them established. Single parameter optimization was performed targeting the ideal slope of the regression line. Results of this optimization provided original NOx and SO2 emission factors for Kolubara lignite.

  10. Biotechnological lignite conversion - a large-scale concept

    Energy Technology Data Exchange (ETDEWEB)

    Reich-Walber, M.; Meyrahn, H.; Felgener, G.W. [Rheinbraun AG, Koeln (Germany). Fuel Technology and Lab. Dept.

    1997-12-31

    Concerning the research on biotechnological lignite upgrading, Rheinbraun`s overall objective is the large-scale production of liquid and gaseous products for the energy and chemical/refinery sectors. The presentation outlines Rheinbraun`s technical concept for electricity production on the basis of biotechnologically solubilized lignite. A first rough cost estimate based on the assumptions described in the paper in detail and compared with the latest power plant generation shows the general cost efficiency of this technology despite the additional costs in respect of coal solubilization. The main reasons are low-cost process techniques for coal conversion on the one hand and cost reductions mainly in power plant technology (more efficient combustion processes and simplified gas clean-up) but also in coal transport (easy fuel handling) on the other hand. Moreover, it is hoped that an extended range of products will make it possible to widen the fields of lignite application. The presentation also points out that there is still a huge gap between this scenario and reality by limited microbiological knowledge. To close this gap Rheinbraun started a research project supported by the North-Rhine Westphalian government in 1995. Several leading biotechnological companies and institutes in Germany and the United States are involved in the project. The latest results of the current project will be presented in the paper. This includes fundamental research activities in the field of microbial coal conversion as well as investigations into bioreactor design and product treatment (dewatering, deashing and desulphurization). (orig.)

  11. Thermal dewatering of lignite: Phase III - final report

    Energy Technology Data Exchange (ETDEWEB)

    Champagne, P J; Szladow, A J; Kybett, B D

    1981-01-01

    Phase III of this project extended the investigation of thermal dewatering on several lignite and peat samples at the temperature range up to 400 degrees C and investigated variables such as retention time, increased rates of heating and cooling, extent of trace element removal, effect of particle size and effect of dewatering under heavy and light oils. Lignites from three areas of Canada (Estevan and Coronach, Saskatchewan, and Onakawana, Ontario) and one peat sample (Garrick, Saskatchewan) were thermally dewatered. The equilibrium moisture values obtained for the dewatered products were as low as, or lower than those obtained in Phases I and II of this project (350 degrees C). However, the measured moisture contents of the thermally dewatered Saskatchewan lignites were somewhat higher than those measured in Phases I and II. The equilibrium moisture values and the moisture contents decreased with increasing temperature. An optimum balance between extent of dewatering and resulting steam pressures is obtained for a dewatering temperature between 300 and 350 degrees C. At these temperatures, residence times in the order of 15 minutes are required. (35 refs.)

  12. Effect of biomass on burnouts of Turkish lignites during co-firing

    International Nuclear Information System (INIS)

    Haykiri-Acma, H.; Yaman, S.

    2009-01-01

    Co-firing of some low quality Turkish lignites with woody shells of sunflower seed was investigated via non-isothermal thermogravimetric analysis method. For this purpose, Yozgat-Sorgun, Erzurum-Askale, Tuncbilek, Gediz, and Afsin-Elbistan lignites were selected, and burnouts of these lignites were compared with those of their blends. Biomass was blended as much as 10 and 20 wt.% of the lignites, and heating was performed up to 900 deg. C at a heating rate of 40 deg. C/min under dry air flow of 40 mL/min. This study revealed that the same biomass species may have different influences on the burnout yields of the lignites. Burnouts of Erzurum-Askale lignite increased at any temperature with the increasing ratio of biomass in the blend, whereas burnout yields of other lignites decreased to some extent. Nevertheless, the blends of Turkish lignites with sunflower seed shell did not behave in very different way, and it can be concluded that they are compatible in terms of burnouts for co-combustion in a combustion system. Although the presence of biomass in the lignite blends caused to some decreases in the final burnouts, the carbon dioxide neutral nature of biomass should be taken into account, and co-combustion is preferable for waste-to-energy-management.

  13. Effect of biomass on burnouts of Turkish lignites during co-firing

    Energy Technology Data Exchange (ETDEWEB)

    Haykiri-Acma, H.; Yaman, S. [Istanbul Technical Univ., Chemical and Metallurgical Engineering Faculty, Chemical Engineering Dept., 34469 Maslak, Istanbul (Turkey)

    2009-09-15

    Co-firing of some low quality Turkish lignites with woody shells of sunflower seed was investigated via non-isothermal thermogravimetric analysis method. For this purpose, Yozgat-Sorgun, Erzurum-Askale, Tuncbilek, Gediz, and Afsin-Elbistan lignites were selected, and burnouts of these lignites were compared with those of their blends. Biomass was blended as much as 10 and 20 wt.% of the lignites, and heating was performed up to 900 C at a heating rate of 40 C/min under dry air flow of 40 mL/min. This study revealed that the same biomass species may have different influences on the burnout yields of the lignites. Burnouts of Erzurum-Askale lignite increased at any temperature with the increasing ratio of biomass in the blend, whereas burnout yields of other lignites decreased to some extent. Nevertheless, the blends of Turkish lignites with sunflower seed shell did not behave in very different way, and it can be concluded that they are compatible in terms of burnouts for co-combustion in a combustion system. Although the presence of biomass in the lignite blends caused to some decreases in the final burnouts, the carbon dioxide neutral nature of biomass should be taken into account, and co-combustion is preferable for waste-to-energy-management. (author)

  14. Ameliorative properties of lignite fly ash in reclaiming saline and alkali soils

    Energy Technology Data Exchange (ETDEWEB)

    Mahalingam, P K

    1973-08-01

    Statistical analysis of the yield of rice grain and straw reveals that there is a significant increase in the yield of grain and straw due to the application of lignite fly ash over controls and application of lignite fly ash either at 5 tons or 10 tons per acre was on par with gypsum application at 5 tons/acre. Maximum yield was recorded in treatment with 5 tons of daincha plus 5 tons of lignite fly ash per acre. This is due to the combined effect of green manure and lignite fly ash. 4 references, 3 tables.

  15. JV Task 98 - Controlling Mercury Emissions for Utilities Firing Lignites from North America

    Energy Technology Data Exchange (ETDEWEB)

    Steven Benson

    2007-06-15

    This project compiled and summarized the findings and conclusions of research, development, and demonstration projects on controlling mercury from lignite coals. A significant amount of work has been conducted since 1994 on mercury in lignite, mercury measurement in flue gases, sorbent, sorbent enhancement additives, oxidation agent development, and full-scale demonstration of mercury control technologies. This report is focused on providing the lignite industry with an understanding of mercury issues associated with the combustion of lignite, as well as providing vital information on the methods to control mercury emissions in coal-fired power plants.

  16. Perspectives of the German lignite industry 2014; Perspektiven der deutschen Braunkohlenindustrie 2014

    Energy Technology Data Exchange (ETDEWEB)

    Hartung, Matthias; Milojcic, George [DEBRIV, Koeln (Germany)

    2014-11-01

    The decision to phase out nuclear energy and gradually realign the electricity system towards more renewables in the future required some extensive changes to electricity generation transmission. One of the issues to be considered is what role lignite can play in the transformation of the electricity system and what application is offered to Germany and its regions. However, lignite has some stable factors and their development is fairly predictable. Domestic lignite is one such example. Beyond its familiar attributes, 'secure, competitive and economically important for the regions', 'flexibility' is a key word that indicates a new dimension for the German lignite industry.

  17. Design guidelines for multi-seam mining at Elliot Lake

    International Nuclear Information System (INIS)

    Hedley, D.G.F.

    1978-04-01

    With the current expansion in uranium mining, multi-seam mining could again be practised at Elliot Lake as it was in the 1960s. Information on the dimensions of stopes, pillars, and parting zone was gathered from plans and sections of the relevant closed mines. Discussions were held with personnel familiar with these mines to establish instances of pillar, roof, and parting zone failures. Design guidelines are formulated for stope and pillar dimensions in multi-seam mining for a range of orebody configurations using past practice in a back-analysis approach. Constraints imposed by dip and seam thickness on the choice of equipment and mining layout are evaluated. An attempt is made to bring together the engineering aspects, including rock mechanics, of multi-seam mine design with uranium recovery and other economic factors for three alternative mine layouts: single-seam mining, double-seam mining, and seams-and-parting mining. A series of examples are worked through, showing how the design guidelines can be applied for typical orebody configurations

  18. Dismantling and ploughing under of the Union 103 underground mine in the Hambach opencast mine; Rueckbau und Ueberbaggerung der Tiefbaugrube Union 103 im Tagebau Hambach

    Energy Technology Data Exchange (ETDEWEB)

    Hempel, Ralf [RWE Power AG, Sparte Tagebau Bergheim (DE). Abt. Bergtechnik (PCS-B); Houben, Bernd [RWE Power AG, Tagebau Hambach, Niederzier (DE). Abt. Bergbau (BCH-BT)

    2012-01-15

    As early as the first decades of the past century, Germany as an industrial location strove to achieve a largely independent raw material supply. In this context, a project on underground mining of lignite in the Rhenish lignite mining area - in the region of today's Hambach opencast mine - was launched. The 'Union 103' lignite underground mine near the township of Morschenich was established. Mining work at the Union 103 colliery was confined to the sinking of two shafts down to a depth of 330 m and the construction of roadways with a length of some 11 km. Repeated inflow of water and insufficient profitability led to the closure of the colliery only a few years later in 1955 before the start of regular mining activities. The advancing Hambach opencast mine reached the Union 103 colliery in March 2011. Basic studies were performed to develop a concept for cutting free and dismantling the roadways and shafts. Accompanying exploratory measures to determine the support condition of the mine workings were carried out as well. A report on the current status of the dismantling work and preparatory execution engineering has been provided. (orig.)

  19. Geostatistics applied in mine production planning

    Energy Technology Data Exchange (ETDEWEB)

    Zerdin, F.; Markic, S.; Subelj, A. [NTF, Ljubljana (Slovenia)

    1998-07-01

    Long-term plan for lignite mine Velenje has been made by using a technical 'parametrisation' method where the basis for periodic, middle-term and short-term plans as well as for scheduling has already been fixed. Plans are presented by grade (heating value in GJ), quantity of ROM coal in tons and quantity of excavated material in cubic metre for each sequence of the seam or whole seam as well as for all working seams in the mines as a whole which correspond to a defined time period. Grade planning aims at achieving uniform product quality to meet contractual obligations. 17 refs., 10 figs.

  20. Genetic relationship of organic bases of the quinoline and isoquinoline series from lignite semicoking tars with the initial biological material

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Proskuryakov, V.A.; Podshibyakin, S.I.; Domogatskii, V.V.; Shvykin, A.Y.; Shavyrina, O.A.; Chilachava, K.B. [Leo Tolstoy State Pedagog University, Tula (Russian Federation)

    2002-07-01

    The genetic relationship of quinoline and isoquinoline compounds present in semicoking tars of Kimovsk lignites (near-Moscow fields) with the initial vegetable material is discussed. Transformation pathways of the native compounds in the course of lignite formation are suggested.

  1. Geomechanics of the Climax mine-by, Nevada Test Site

    International Nuclear Information System (INIS)

    Heuze, F.E.

    1981-03-01

    A generic test of retrievable geologic storage of spent fuel assemblies in an underground chamber is being conducted at the Nevada Test Site. The horizontal shrinkage of the pillars is not explainable, but the vertical pillar stresses are easily understood. A two-phase project was initiated to estimate the in-situ deformability of the Climax granite and to refine the in-situ stress field data, and to model the mine-by

  2. Analysis and Optimization of Entry Stability in Underground Longwall Mining

    Directory of Open Access Journals (Sweden)

    Yubing Gao

    2017-11-01

    Full Text Available For sustainable utilization of limited coal resources, it is important to increase the coal recovery rate and reduce mine accidents, especially those occurring in the entry (gateroad. Entry stabilities are vital for ventilation, transportation and other essential services in underground coal mining. In the present study, a finite difference model was built to investigate stress evolutions around the entry, and true triaxial tests were carried out at the laboratory to explore entry wall stabilities under different mining conditions. The modeling and experimental results indicated that a wide coal pillar was favorable for entry stabilities, but oversize pillars caused a serious waste of coal resources. As the width of the entry wall decreased, the integrated vertical stress, induced by two adjacent mining panels, coupled with each other and experienced an increase on the entry wall, which inevitably weakened the stability of the entry. Therefore, mining with coal pillars always involves a tradeoff between economy and safety. To address this problem, an innovative non-pillar mining technique by optimizing the entry surrounding structures was proposed. Numerical simulation showed that the deformation of the entry roof decreased by approximately 66% after adopting the new approach, compared with that using the conventional mining method. Field monitoring indicated that the stress condition of the entry was significantly improved and the average roof pressure decreased by appropriately 60.33% after adopting the new technique. This work provides an economical and effective approach to achieve sustainable exploitation of underground coal resources.

  3. Geotechnical design of underground slate mines

    International Nuclear Information System (INIS)

    Iglesias Comesaña, C.; Taboada Castro, J.; Arzúa Touriño, J.; Giráldez Pérez, E.; Martín Suárez, J.M.

    2017-01-01

    Slate is one of the most important natural materials in Spain, with a potent extractive and processing industry concentrated in the autonomous communities of Galicia, Castile and León. Thanks to its resistance to external agents, its impermeability and its excellent cleavability, slate is used as for roofing and tiling. Almost all the active exploitations in our country where this resource is extracted are open pit mines, where the exploitation ratios have nearly reached their economic limit, making it necessary to look for alternatives that will allow the mining works to be continued. Underground mining is a solution that offers low exploitation ratios, with low spoil generation. The room-and-pillar method with barrier pillars is usually applied for the exploitation of slate deposits. There are several factors to be taken into account when designing a mine (economic, logistical, geotechnical, technical, environmental…), especially for an underground mine. This study focuses on the geotechnical design process of a room-and-pillar underground mine, based on the tributary area theory, the analysis of the tensions in the ground with numerical methods and the choice of an appropriate reinforcement in view of the expected instabilities. This explanation is completed with an example of a design that includes the estimate exploitation rates and production. [es

  4. POROUS MEMBRANE TEMPLATED SYNTHESIS OF POLYMER PILLARED LAYER

    Institute of Scientific and Technical Information of China (English)

    Zhong-wei Niu; Dan Li; Zhen-zhong Yang

    2003-01-01

    The anodic porous alumina membranes with a definite pore diameter and aspect ratio were used as templates to synthesize polymer pillared layer structures. The pillared polymer was produced in the template membrane pores, and the layer on the template surfaces. Rigid cured epoxy resin, polystyrene and soft hydrogel were chosen to confirm the methodology. The pillars were in the form of either tubes or fibers, which were controlled by the alumina membrane pore surface wettability. The structural features were confirmed by scanning electron microscopy results.

  5. Biodegradation of photo-oxidized lignite and characterization of the products

    Science.gov (United States)

    Li, Jiantao; Liu, Xiangrong; Yue, Zilin; Zhang, Yaowen

    2018-01-01

    Biodegradation of photo-oxidized Inner Mongolia lignite by pseudomonas aeruginosa was studied and the degradation percentage reached 56.27%, while the corresponding degradation percentage of the strain degrading raw Inner Mongolia lignite is only 23.16%. The degradation products were characterized. Proximate and ultimate analyses show that the higher oxygen content increased by photo-oxidation pretreatment maybe promoted the degradation process. Ultraviolet spectroscopy (UV) analysis of the liquid product reveals that it contains unsaturated structures and aromatic rings are the main structure units. Gas chromatography-mass spectrometry (GC-MS) analysis indicates that the main components of the ethyl acetate extracts are low molecular weight organic compounds, such as ketones, acids, hydrocarbons, esters and alcohols. Infrared spectroscopy (IR) analysis of raw lignite, photo-oxidized lignite and residual lignite demonstrates that the absorption peaks of functional groups in residual lignite disappeared or weakened obviously. Scanning electron microscopy (SEM) analysis manifests that small holes appear in photo-oxidized lignite surface, which may be promote the degradation process and this is only from the physical morphology aspects, so it can be inferred from the tests and analyses results that the more important reason of the high degradation percentage is mostly that the photo-oxidation pretreatment changes the chemical structures of lignite.

  6. Solid substrate fermentation of lignite by the coal-solubilizing mould, Trichoderma atroviride, in a new type of bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Holker, U.; Hofer, M. [University of Bonn, Bonn (Germany)

    2002-07-01

    Trichoderma atroviride CBS 349 is able to solubilize lignite. The mould was cultured under non-sterile conditions in a new type of bioreactor for solid substrate fermentation. German lignite (lithotype A, Bergheim) was used as complex solid substrate. Over 40 days 140 g of 1.5 kg lignite held in a 25 1-bioreactor was solubilized by the fungus.

  7. Sedimentologic and palynologic significance of finding tertiary lignites in an ancient rift zone lake (Chingla, Ethiopia). Vol. 2

    Energy Technology Data Exchange (ETDEWEB)

    Kedamawit, Y.; Bonnefille, R.; Faure, H.; Taieb, M.

    1984-01-01

    Oligocene-Pleistocene deposits at Chingla apparently lie atop Miocene basalts. The upper cross-section shows numerous lignite interlayers. This paper discusses mineral composition of lignites and enclosing rock. Palynologic analysis of the lignite cross-sections determined 23 layers.

  8. The old pillars of new retailing.

    Science.gov (United States)

    Berry, L L

    2001-04-01

    Despite the harsh realities of retailing, the illusion persists that magical tools can help companies overcome the problems of fickle consumers, price-slashing competitors, and mood swings in the economy. Such wishful thinking holds that retailers will thrive if only they communicate better with customers through e-mail, employ hidden cameras to learn how customers make purchase decisions, and analyze scanner data to tailor special offers and manage inventory. But the truth is, there are no quick fixes. In the course of his extensive research on dozens of retailers, Leonard Berry found that the best companies create value for their customers in five interlocking ways. Whether you're running a physical store, a catalog business, an e-commerce site, or a combination of the three, you have to offer your customers superior solutions to their needs, treat them with respect, and connect with them on an emotional level. You also have to set prices fairly and make it easy for people to find what they need, pay for it quickly, and then move on. None of these pillars is new, and each sounds exceedingly simple, but don't be fooled--implementing these axioms in the real world is surprisingly difficult. The author illustrates how some retailers have built successful operations by attending to these commonsense ways of dealing with their customers and how others have failed to do so.

  9. JV Task 90 - Activated Carbon Production from North Dakota Lignite

    Energy Technology Data Exchange (ETDEWEB)

    Steven Benson; Charlene Crocker; Rokan Zaman; Mark Musich; Edwin Olson

    2008-03-31

    The Energy & Environmental Research Center (EERC) has pursued a research program for producing activated carbon from North Dakota lignite that can be competitive with commercial-grade activated carbon. As part of this effort, small-scale production of activated carbon was produced from Fort Union lignite. A conceptual design of a commercial activated carbon production plant was drawn, and a market assessment was performed to determine likely revenue streams for the produced carbon. Activated carbon was produced from lignite coal in both laboratory-scale fixed-bed reactors and in a small pilot-scale rotary kiln. The EERC was successfully able to upgrade the laboratory-scale activated carbon production system to a pilot-scale rotary kiln system. The activated carbon produced from North Dakota lignite was superior to commercial grade DARCO{reg_sign} FGD and Rheinbraun's HOK activated coke product with respect to iodine number. The iodine number of North Dakota lignite-derived activated carbon was between 600 and 800 mg I{sub 2}/g, whereas the iodine number of DARCO FGD was between 500 and 600 mg I{sub 2}/g, and the iodine number of Rheinbraun's HOK activated coke product was around 275 mg I{sub 2}/g. The EERC performed both bench-scale and pilot-scale mercury capture tests using the activated carbon made under various optimization process conditions. For comparison, the mercury capture capability of commercial DARCO FGD was also tested. The lab-scale apparatus is a thin fixed-bed mercury-screening system, which has been used by the EERC for many mercury capture screen tests. The pilot-scale systems included two combustion units, both equipped with an electrostatic precipitator (ESP). Activated carbons were also tested in a slipstream baghouse at a Texas power plant. The results indicated that the activated carbon produced from North Dakota lignite coal is capable of removing mercury from flue gas. The tests showed that activated carbon with the greatest

  10. Methodology for quantifying uncertainty in coal assessments with an application to a Texas lignite deposit

    Energy Technology Data Exchange (ETDEWEB)

    Olea, Ricardo A.; Luppens, James A.; Tewalt, Susan J. [U.S. Geological Survey, Reston, VA (United States)

    2011-01-01

    A common practice for characterizing uncertainty in coal resource assessments has been the itemization of tonnage at the mining unit level and the classification of such units according to distance to drilling holes. Distance criteria, such as those used in U.S. Geological Survey Circular 891, are still widely used for public disclosure. A major deficiency of distance methods is that they do not provide a quantitative measure of uncertainty. Additionally, relying on distance between data points alone does not take into consideration other factors known to have an influence on uncertainty, such as spatial correlation, type of probability distribution followed by the data, geological discontinuities, and boundary of the deposit. Several geostatistical methods have been combined to formulate a quantitative characterization for appraising uncertainty. Drill hole datasets ranging from widespread exploration drilling to detailed development drilling from a lignite deposit in Texas were used to illustrate the modeling. The results show that distance to the nearest drill hole is almost completely unrelated to uncertainty, which confirms the inadequacy of characterizing uncertainty based solely on a simple classification of resources by distance classes. The more complex statistical methods used in this study quantify uncertainty and show good agreement between confidence intervals in the uncertainty predictions and data from additional drilling. (author)

  11. Methodology for quantifying uncertainty in coal assessments with an application to a Texas lignite deposit

    Science.gov (United States)

    Olea, R.A.; Luppens, J.A.; Tewalt, S.J.

    2011-01-01

    A common practice for characterizing uncertainty in coal resource assessments has been the itemization of tonnage at the mining unit level and the classification of such units according to distance to drilling holes. Distance criteria, such as those used in U.S. Geological Survey Circular 891, are still widely used for public disclosure. A major deficiency of distance methods is that they do not provide a quantitative measure of uncertainty. Additionally, relying on distance between data points alone does not take into consideration other factors known to have an influence on uncertainty, such as spatial correlation, type of probability distribution followed by the data, geological discontinuities, and boundary of the deposit. Several geostatistical methods have been combined to formulate a quantitative characterization for appraising uncertainty. Drill hole datasets ranging from widespread exploration drilling to detailed development drilling from a lignite deposit in Texas were used to illustrate the modeling. The results show that distance to the nearest drill hole is almost completely unrelated to uncertainty, which confirms the inadequacy of characterizing uncertainty based solely on a simple classification of resources by distance classes. The more complex statistical methods used in this study quantify uncertainty and show good agreement between confidence intervals in the uncertainty predictions and data from additional drilling. ?? 2010.

  12. Treatment of products from petroleum, shale, coal, lignite, etc

    Energy Technology Data Exchange (ETDEWEB)

    Jevanoff, V

    1952-06-20

    An improved process is described for treating with sodium plumbite all the products derived from crude petroleum, bituminous shale, coal, lignite, peat, etc., such as gasoline, solvents, lamp oil, gas oil, fuels, etc; the process being essentially characterized by the fact that it consists first in washing the product to be refined with a soda wash; submitting it to a treatment with sodium plumbite, without addition of sulfur, then to eliminate the sulfur plumbite compounds resulting in the treated product, using either redistillation to eliminate products remaining in the residue or filtration over an absorbing material such as active carbon, decolorizing earths.

  13. EFFECT OF MICROWAVE DRYING ON THE GRINDABILITY OF LIGNITE COAL

    OpenAIRE

    Güngören, Can; Özkan, Şafak Gökhan; Hacıfazlıoğlu, Hasan

    2016-01-01

    In this study, the representative lignite coal samples supplied from Kastamonu-Tosya region were dried in a conventional drying oven and a microwave oven, and then they were ground by a laboratory rod mill. The particle size analyses of the ground samples at various grinding times (10, 20, 30, and 60 minutes) were carried out, and the results were compared. As a result, the d80 particle sizes of the samples, dried in the conventional drying oven, were determined as 350, 183, 180, and 100 µm a...

  14. Refining of raw materials, lignite present economic problems

    Energy Technology Data Exchange (ETDEWEB)

    Schirmer, G.

    1985-06-01

    East Germany seeks an economic intensification program that involves refining raw materials to a higher level. Lignite briquetting prior to liquefaction and gasification illustrates both the theoretical and practical aspects of that goal and also introduces questions of secure supplies. The author describes the special labor processes, use of technology, recycling of waste materials, and other new problems that the approach entails as the refined raw materials become new materials or energy sources. Economics based on the value of the refined product and the cost of the materials determine the degree of refinement. The concept also involves the relationship of producer and user as profits increase.

  15. Quantitative spectrographic determination of traces of germanium in lignite

    International Nuclear Information System (INIS)

    Martin, M.; Roca, M.

    1972-01-01

    A burning technique in a d.c. arc at 10 amp has been employed. The standards have been prepared from a natural lignite with a low germanium content. In order to enhance sensitivity, AgCl, K 2 SO 4 , CuF 2 , Sb 2 S 3 and Bi 2 S 3 have been tested as sweeping materials. Using 2% CuF 2 a detection limit of 1 ppm germanium is attainable. Bi, Cu, Sb and Sn have been studied as internal standards: the former leads to the, highest precision (1 6%. Results show good agreement with those obtained by the addition method. (Author) 6 refs

  16. The structure and pyrolysis product distribution of lignite from different sedimentary environment

    International Nuclear Information System (INIS)

    Liu, Peng; Zhang, Dexiang; Wang, Lanlan; Zhou, Yang; Pan, Tieying; Lu, Xilan

    2016-01-01

    Highlights: • Carbon structure of three lignites was measured by solid "1"3C NMR. • Effect of carbon structure on pyrolysis product distribution was studied. • Tar yield is influenced by aliphatic carbon and oxygen functional group. • C1–C4 content of pyrolysis gas is related to CH_2/CH_3 ratio. - Abstract: Low-temperature pyrolysis is an economically efficient method for lignite to obtain coal tar and improve its combustion calorific value. The research on the distribution of pyrolysis product (especially coal tar yield) plays an important role in energy application and economic development in the now and future. Pyrolysis test was carried out in a tube reactor at 873 K for 15 min. The structure of the lignite was measured by solid "1"3C nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopy (FTIR). The thermal analysis was analyzed by thermo-gravimetric (TG) analyzer. The results show that the pyrolysis product distribution is related to the breakage of branch structures of aromatic ring in lignites from different sedimentary environment. The gas yield and composition are related to the decomposition of carbonyl group and the breakage of aliphatic carbon. The tar yield derived from lignite pyrolysis follows the order: Xianfeng lignite (XF, 13.67 wt.%) > Xiaolongtan lignite (XLT, 7.97 wt.%) > Inner Mongolia lignite (IM, 6.30 wt.%), which is mainly influenced by the aliphatic carbon contents, the CH_2/CH_3 ratio and the oxygen functional groups in lignite. The pyrolysis water yield depends on the decomposition of oxygen functional groups. IM has the highest content of oxygen-linked carbon so that the pyrolysis water yield derived from IM is the highest (9.20 wt.%), and is far more than that from the other two lignites.

  17. PS buildings : reinforced concrete structure for shielding "bridge" pillar

    CERN Multimedia

    CERN PhotoLab

    1956-01-01

    The PS ring traverses the region between the experimental halls South and North (buildings Nos 150 and 151) under massive bridge-shaped concrete beams. This pillar stands at the S-W end of the structure.

  18. Lignite pre-treatment and its effect on bio-stimulative properties of respective lignite humic acids

    Energy Technology Data Exchange (ETDEWEB)

    Vlckova, Z.; Grasset, L.; Antosova, B.; Pekar, M.; Kucerik, J. [Brno University of Technology, Brno (Czech Republic). Faculty of Chemistry

    2009-09-15

    Humic acids originating from South-Moravian lignite were subjected to a comparative study with the aim to assess the alteration of their physico-chemical properties after various lignite pre-treatments. Physical modification was achieved with two organic acids, such as acetic acid and citric acid and chemical modification by nitric acid and hydrogene peroxide in various concentrations. Elemental analysis, solid-state NMR, GC-MS analysis of polyols and size exclusion chromatography were carried out for chemical-physical characterization of obtained humic acids. Their biological effect, in form of potassium and ammonium humates, was tested on maize (Zea mays) seedlings. In these tests, potassium humates achieved far better overall results than ammonium humates. Results were inter-correlated in order to appraise the influence of humic acids physical and chemical properties on biological activity. Surprisingly, fractions with the lowest molecular size (0-35 kDa) showed no correlation with bioactivity results (Pearson coefficient from 0.05 to -0.4). On the contrary, middle-sized fractions (35-175 kDa) showed highly significant positive correlation (Pearson coefficient up to 0.92) and the highest molecular-size-fractions (275-350 kDa) showed negative correlation (Pearson coefficient up to -0.75). These findings were identical for both potassium and ammonium humates. No connection was found between bioactivity of humates and polyols content which was remarkably high; it reached 150 mg per g of humic acids in the most extreme case of 5% hydrogene peroxide pre-treatment. In the final analysis, the preparation mode bore pivotal responsibility for the control of humic acids biological effect and showed the best results for potassium humates obtained from lignite pre-treated by acetic acid and by 2% hydrogen peroxide.

  19. Co-pyrolysis of lignite and sugar beet pulp

    International Nuclear Information System (INIS)

    Yilgin, M.; Deveci Duranay, N.; Pehlivan, D.

    2010-01-01

    Today, worldwide studies have been undertaken on the biomass usage and co-conversion of biomass and coal to seek out alternative fuels for supplying energy in an environmental friendly way. The objective of this work is to study co-pyrolysis of lignite and sugar beet pulp in 50/50 (wt./wt.) ratio of blend pellets, to elucidate their thermal behaviour under pyrolysis conditions and to assess major decomposition products in terms of their yields. A special chamber, which has enabled very fast heating rates, was used in the pyrolysis experiments carried at 600 deg. C. The results were interpreted in the light of liquid, solid and gaseous yields, resulting from thermal decomposition, and kinetics of thermogravimetric analysis. Proximate volatile matter and ash contents of the blends were different compared to those found by using individual values. Sugar beet pulp decomposed faster within a relatively narrow temperature range than lignite and underwent a significant shrinkage during pyrolysis. It was found that the chars left behind after the flash pyrolysis of these pellets at 600 deg. C have substantial amounts of volatile matter that would evolve upon further heating.

  20. The hydrogasification of lignite and sub-bituminous coals

    Science.gov (United States)

    Bhatt, B.; Fallon, P. T.; Steinberg, M.

    1981-02-01

    A North Dakota lignite and a New Mexico sub-bituminous coal have been hydrogenated at up to 900°C and 2500 psi hydrogen pressure. Yields of gaseous hydrocarbons and aromatic liquids have been studied as a function of temperature, pressure, residence time, feed rates and H2/coal ratio. Coal feed rates in excess of 10 lb/hr have been achieved in the 1 in. I. D.×8 ft reactor and methane concentration as high as 55% have been observed. A four-step reaction model was developed for the production and decomposition of the hydrocarbon products. A single object function formulated from the weighted errors for the four dependent process, variables, CH4, C2H6, BTX, and oil yields, was minimized using a program containing three independent iterative techniques. The results of the nonlinear regression analysis for lignite show that a first-order chemical reaction model with respect to C conversion satisfactorily describes the dilute phase hydrogenation. The activation energy for the initial products formation was estimated to be 42,700 cal/gmole and the power of hydrogen partial pressure was found to be +0.14. The overall correlation coefficient was 0.83. The mechanism, the rate expressions, and the design curves developed can be used for scale-up and reactor design.

  1. Exergy Analysis of Operating Lignite Fired Thermal Power Plant

    Directory of Open Access Journals (Sweden)

    K. Murugesan

    2009-01-01

    Full Text Available The energy assessment must be made through the energy quantity as well as the quality. But the usual energy analysisevaluates the energy generally on its quantity only. However, the exergy analysis assesses the energy on quantity as well asthe quality. The aim of the exergy analysis is to identify the magnitudes and the locations of real energy losses, in order toimprove the existing systems, processes or components. The present paper deals with an exergy analysis performed on anoperating 50MWe unit of lignite fired steam power plant at Thermal Power Station-I, Neyveli Lignite Corporation Limited,Neyveli, Tamil Nadu, India. The exergy losses occurred in the various subsystems of the plant and their components havebeen calculated using the mass, energy and exergy balance equations. The distribution of the exergy losses in several plantcomponents during the real time plant running conditions has been assessed to locate the process irreversibility. The Firstlaw efficiency (energy efficiency and the Second law efficiency (exergy efficiency of the plant have also been calculated.The comparison between the energy losses and the exergy losses of the individual components of the plant shows that themaximum energy losses of 39% occur in the condenser, whereas the maximum exergy losses of 42.73% occur in the combustor.The real losses of energy which has a scope for the improvement are given as maximum exergy losses that occurredin the combustor.

  2. On the consideration of geological uncertainties in the evaluation of lignite deposits; Zur Beruecksichtigung geologischer Ungewissheit in der Bewertung von Braunkohlevorkommen

    Energy Technology Data Exchange (ETDEWEB)

    Benndorf, Joerg [Technische Univ. Delft (Netherlands). Dept. of Geosciences and Engineering; Naworyta, Wojciech [AGH Univ. of Science and Technology, Cracow (Poland). Dept. of Open Pit Mining

    2012-12-15

    All phases of planning as well as the operational open-cast mining require a sufficient knowledge on the spatial distribution of the properties of deposits with respect to quality and geometrical structure. This knowledge is a requisition to a sustainable and optimal utilization of lignite as a raw material under security-related and economic aspects. The spatial distribution of the deposit based on exploration data utilizing different methods of interpolation is recognized as a planning framework and also illustrated in a three-dimensional model. The geo-statistics offers different approaches of modelling whereby at each time the specific tasks and aims specify the selection of the specific methodology. Under this aspect, the authors of the contribution under consideration compare different approaches of methodology with actual analyses using a deposit in Central Europe as a case study. These approaches of methodology are evaluated under the criteria of the prediction accuracy as well as their derivability from exceeding probabilities and lower deviation probabilities of threshold values. The results of this investigation give information about the profitability of certain concepts in the lignite mining.

  3. Current practice and guidelines for the safe design of water barrier pillars

    CSIR Research Space (South Africa)

    Rangasamy, T

    2001-08-01

    Full Text Available adjacent to barrier pillars was conducted to ascertain the relationship between compartment water head, barrier pillar width and flow rates for combinations of roof bound, coal bound and floor bound flow. The results obtained from the instrumentation... pillars. A survey of South African Collieries revealed that water leakage associated with barrier pillars can be classed into seven predominant geotechnical flow categories. Through extensive numerical modelling and case history matching, barrier pillar...

  4. Energy and water conservation at lignite-fired power plants using drying and water recovery technologies

    International Nuclear Information System (INIS)

    Liu, Ming; Qin, Yuanzhi; Yan, Hui; Han, Xiaoqu; Chong, Daotong

    2015-01-01

    Highlights: • Pre-drying and water recovery technologies were used to conserve energy and water. • The energy and water conservation potential were analyzed with reference cases. • The air-cooling unit produces water when the water content of lignite is high enough. • Influences of main parameters on energy and water conservation were analyzed. - Abstract: Lignite is considered as a competitive energy raw material with high security of supply viewed from a global angle. However, lignite-fired power plants have many shortcomings, including high investment, low energy efficiency and high water use. To address these issues, the drying and water recovery technologies are integrated within lignite-fired power plants. Both air-cooling and wet-cooling units with three kinds of lignite as feeding fuel were analyzed quantitatively. Results showed that energy conservation and water conservation are obtained simultaneously. The power plant firing high moisture lignite becomes more environmental friendly with higher power generation efficiency and a lower water makeup rate than the one firing low moisture lignite. And further calculation revealed that the air-cooling unit needs no makeup water and even produces some water as it generates power, when the water carrying coefficient is higher than 40 g/MJ.

  5. Characteristics of Mae Moh lignite: Hardgrove grindability index and approximate work index

    Directory of Open Access Journals (Sweden)

    Wutthiphong Tara

    2012-02-01

    Full Text Available The purpose of this research was to preliminarily study the Mae Moh lignite grindability tests emphasizing onHardgrove grindability and approximate work index determination respectively. Firstly, the lignite samples were collected,prepared and analyzed for calorific value, total sulfur content, and proximate analysis. After that the Hardgrove grindabilitytest using ball-race test mill was performed. Knowing the Hardgrove indices, the Bond work indices of some samples wereestimated using the Aplan’s formula. The approximate work indices were determined by running a batch dry-grinding testusing a laboratory ball mill. Finally, the work indices obtained from both methods were compared. It was found that allsamples could be ranked as lignite B, using the heating value as criteria, if the content of mineral matter is neglected. Similarly,all samples can be classified as lignite with the Hargrove grindability indices ranging from about 40 to 50. However, there isa significant difference in the work indices derived from Hardgrove and simplified Bond grindability tests. This may be due todifference in variability of lignite properties and the test procedures. To obtain more accurate values of the lignite workindex, the time-consuming Bond procedure should be performed with a number of corrections for different milling conditions.With Hardgrove grindability indices and the work indices calculated from Aplan’s formula, capacity of the roller-racepulverizer and grindability of the Mae Moh lignite should be investigated in detail further.

  6. Eocene Yegua Formation (Claiborne group) and Jackson group lignite deposits of Texas

    Science.gov (United States)

    Hook, Robert W.; Warwick, Peter D.; Swanson, Sharon M.; Hackley, Paul C.; Warwick, Peter D.; Karlsen, Alexander K.; Merrill, Matthew D.; Valentine, Brett J.

    2011-01-01

    The lignite deposits within the upper Eocene Yegua Formation (Claiborne Group) and the overlying Jackson Group are among the coal resources that were not quantitatively assessed as part of the U.S. Geological Survey's (USGS) National Coal Resource Assessment (NCRA) program in the Gulf Coastal Plain coal province. In the past, these lignite-bearing stratigraphic units often have been evaluated together because of their geographic and stratigraphic proximity (Fisher, 1963; Kaiser, 1974; Kaiser et al., 1980; Jackson and Garner, 1982; Kaiser, 1996) (Figures 1, 2). The term “Yegua-Jackson trend“ is used informally herein for the lignite-bearing outcrops of these Late Eocene deposits in Texas. Lignite beds in the Yegua-Jackson trend generally are higher both in ash yield and sulfur content than those of the underlying Wilcox Group (Figure 2). Recent studies (Senkayi et al., 1987; Ruppert et al., 1994; Warwick et al., 1996, 1997) have shown that some lignite beds within the Yegua-Jackson trend contain partings of volcanic ash and host elevated levels of trace elements that have been identified as potentially hazardous air pollutants (HAPs) in the United States Clean Air Amendments of 1990. Lignite beds within the Yegua Formation are thin (less than or equal to 6 ft) and laterally discontinuous in comparison with most Wilcox Group deposits (Ayers, 1989a); in contrast, the Jackson Group lignite beds range up to 12 ft in total thickness and are relatively continuous laterally, extending nearly 32 mi along strike.

  7. Findings obtained from the washing of black lignite from Teruel. Experiencias obtenidas en la depuracion mediante lavado de los lignitos negros de Teruel

    Energy Technology Data Exchange (ETDEWEB)

    Suarez Perez, A; Carbajo Josa, J I; Kindelan Alonso, J M; Fernandez Trabanco, J J [ENDESA, Madrid (Spain)

    1989-10-01

    The article summarises findings from ENDESA pilot plant in Andorra (Teruel) during cleaning of black lignite using different types of equipment and washing methods. The project received grants from the Directorate General of Mines, the Aragon Provincial Council, OCIDE and Ocicarbon. Research began in 1984 in the ENADIMSA pilot plant and laboratory and continued with the construction in Andorra of a 5 t/hour pilot plant to which other equipment was later added to give a capacity of 50 t/hour. Currently, the plant continues to treat and investigate various types of coal from the coalfield in order to define washability parameters and obtain data which, using mixtures of coal from various mines, make it possible to achieve optimum results in the 500 t/hour industrial plant which is being built by ENDESA. 1 fig., 4 tabs.

  8. Identification of mine waters by statistical multivariate methods

    Energy Technology Data Exchange (ETDEWEB)

    Mali, N [IGGG, Ljubljana (Slovenia)

    1992-01-01

    Three water-bearing aquifers are present in the Velenje lignite mine. The aquifer waters have differing chemical composition; a geochemical water analysis can therefore determine the source of mine water influx. Mine water samples from different locations in the mine were analyzed, the results of chemical content and of electric conductivity of mine water were statistically processed by means of MICROGAS, SPSS-X and IN STATPAC computer programs, which apply three multivariate statistical methods (discriminate, cluster and factor analysis). Reliability of calculated values was determined with the Kolmogorov and Smirnov tests. It is concluded that laboratory analysis of single water samples can produce measurement errors, but statistical processing of water sample data can identify origin and movement of mine water. 15 refs.

  9. Investigation of pre-drying lignite in an existing Greek power plant

    Directory of Open Access Journals (Sweden)

    Agraniotis Michalis

    2012-01-01

    Full Text Available The application of lignite pre-drying technologies in next generation of lignite power plants by utilizing low pressure steam as a drying medium instead of hot recirculated flue gas - combined with thermal utilization of the vaporized coal moisture - is expected to bring efficiency increase of 2-4 percentage points in future lignite power plants compared with today’s state of the art. The pre-drying concept is of particular importance in Greek boilers firing lignite with a high water and ash content. The combustion of Greek predried lignite has been investigated experimentally and via numerical simulations in our previous research. This study focuses on the potential integration of a lignite pre-drying system in an existing Greek power plant with dry lignite co-firing thermal share of up to 30%. The radiative and convective heat fluxes to the boiler and the overall boiler heat balance is calculated for reference and dry lignite co-firing conditions by an in-house calculation code. The overall plant’s thermal cycle is then simulated using commercial thermal cycle calculation software. The net plant efficiency is in this way determined for reference and dry coal co-firing conditions. According to the simulation results the integration of a pre-drying system and the implementation of dry lignite co-firing may bring an efficiency increase of about 1.5 percentage points in existing Greek boilers. It is therefore considered as an important measure towards improving plant efficiency and reducing specific CO2 emissions in existing plants.

  10. Applications of a computer model to the analysis of rock-backfill interaction in pillar recovery operations

    Energy Technology Data Exchange (ETDEWEB)

    Sinclair, T. J.E. [Dames and Moore, London, England, United Kingdom; Shillabeer, J. H. [Dames and Moore, Toronto (Canada); Herget, G. [CANMET, Ottawa (Canada)

    1980-05-15

    This paper describes the application of a computer model to the analysis of backfill stability in pillar recovery operations with particular reference to two case studies. An explicit finite difference computer program was developed for the purpose of modelling the three-dimensional interaction of rock and backfill in underground excavations. Of particular interest was the mechanics of stress transfer from the rock mass to the pillars and then the backfill. The need, therefore, for a model to allow for the three-dimensional effects and the sequence of operations is evident. The paper gives a brief description of the computer program, descriptions of the mines, the sequences of operations and how they were modelled, and the results of the analyses in graphical form. For both case studies, failure of the backfill was predicted at certain stages. Subsequent reports from the mines indicate that such failures did not occur at the relevant stage. The paper discusses the validity of the model and concludes that the approach accurately represents the principles of rock mechanics in cut-and-fill mining and that further research should be directed towards determining the input parameters to an equal degree of sophistication.

  11. Sulfomethylated lignite salt as a sacrifical agent in oil recovery processes

    Energy Technology Data Exchange (ETDEWEB)

    Kudchadker, M.V.; Weiss, W.J.

    1978-02-07

    A process is described for recovering petroleum from oil reservoirs by secondary recovery methods. The process involves injecting via an injection well into the reservoir an aqueous solution of sulfomethylated lignite salt as a sacrificial agent to inhibit the deposition of surfactant and polymer on the reservoir matrix. The process is conducted by first injecting the lignite salt into the formation through the injection well and following it with either a polymer or a surfactant solution, which also may contain the lignite salt. The polymer or surfactant would then be followed by a drive fluid, such as water, to push the chemicals and oil to the production well. (18 claims)

  12. Bioprocessing of lignite coals using reductive microorganisms. Final technical report, September 30, 1988--March 29, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, D.L.

    1992-03-29

    In order to convert lignite coals into liquid fuels, gases or chemical feedstock, the macromolecular structure of the coal must be broken down into low molecular weight fractions prior to further modification. Our research focused on this aspect of coal bioprocessing. We isolated, characterized and studied the lignite coal-depolymerizing organisms Streptomyces viridosporus T7A, Pseudomonas sp. DLC-62, unidentified bacterial strain DLC-BB2 and Gram-positive Bacillus megaterium strain DLC-21. In this research we showed that these bacteria are able to solubilize and depolymerize lignite coals using a combination of biological mechanisms including the excretion of coal solublizing basic chemical metabolites and extracellular coal depolymerizing enzymes.

  13. Innovative approach to ash radioactivitiy and health impacts of lignite power plants

    Energy Technology Data Exchange (ETDEWEB)

    Bosevski, T.; Pop-Jordanova, N. [Macedonian Academy of Sciences and Arts, Skopje (Macedonia)

    1998-12-31

    In Macedonia nearly 90% of the present electricity production utilizes domestic low-calorie lignite, and this is likely to continue for the next few decades. Local and global environmental impacts of fossil fuel utilization are considered. Some innovative extensions to standard methodologies of environmental risk assessment and management are considered. They involve ash radioactivity and psychosomatic health impacts from lignite power plants. Two extensions are proposed: one comprising complete radioactive chains when determining committed effective dose from lignite ash; the other by including the psychosomatic diseases, such as peptic ulcer and arterial hypertension, due to chronic stress induced by power plants during normal operation. 7 refs., 2 figs., 3 tabs.

  14. Properties and potential of formed cokes derived from two Turkish lignites by carbonization of binderless briquettes

    Energy Technology Data Exchange (ETDEWEB)

    Bayraktur, K.N.; Lawson, G.J.

    1984-09-01

    Two high-sulphur Turkish lignites were briquetted at room temperature under pressures of 113 or 212 MPa and the briquettes were carbonized to 1158-1173 K over special heating cycles. The lowerrank lignite gave a formed coke of superior mechanical strength, lower porosity and higher sulphur content than typical blast furnace cokes. The formed coke produced from the higher-rank lignite briquettes had slightly poorer mechanical strength, lower porosity and much higher ash and sulphur content than conventional cokes. The products were considered attractive for use in non-ferrous metallurgy.

  15. Properties and potential of formed cokes derived from two Turkish lignites by carbonization of binderless briquettes

    Energy Technology Data Exchange (ETDEWEB)

    Bayraktar, K.N.; Lawson, G.J.

    1984-09-01

    Two high-sulphur Turkish lignites were briquetted at room temperature under pressures of 113 or 212 MPa and the briquettes were carbonized to 1158-1173 K over special heating cycles. The lower-rank lignite gave a formed coke of superior mechanical strength, lower porosity and higher sulphur content than typical blast furnace cokes. The formed coke produced from the higher-rank lignite briquettes had slightly poorer mechanical strength, lower porosity and much higher ash yield and sulphur content than conventional cokes. The products were considered attractive for use in non-ferrous metallurgy. 38 references.

  16. JV Task - 129 Advanced Conversion Test - Bulgarian Lignite

    Energy Technology Data Exchange (ETDEWEB)

    Michael Swanson; Everett Sondreal; Daniel Laudal; Douglas Hajicek; Ann Henderson; Brandon Pavlish

    2009-03-27

    The objectives of this Energy & Environmental Research Center (EERC) project were to evaluate Bulgarian lignite performance under both fluid-bed combustion and gasification conditions and provide a recommendation as to which technology would be the most technically feasible for the particular feedstock and also identify any potential operating issues (such as bed agglomeration, etc.) that may limit the applicability of a potential coal conversion technology. Gasification tests were run at the EERC in the 100-400-kg/hr transport reactor development unit (TRDU) on a 50-tonne sample of lignite supplied by the Bulgarian Lignite Power Project. The quality of the test sample was inferior to any coal previously tested in this unit, containing 50% ash at 26.7% moisture and having a higher heating value of 5043 kJ/kg after partial drying in preparation for testing. The tentative conclusion reached on the basis of tests in the TRDU is that oxygen-blown gasification of this high-ash Bulgarian lignite sample using the Kellogg, Brown, and Root (KBR) transport gasifier technology would not provide a syngas suitable for directly firing a gas turbine. After correcting for test conditions specific to the pilot-scale TRDU, including an unavoidably high heat loss and nitrogen dilution by transport air, the best-case heating value for oxygen-blown operation was estimated to be 3316 kJ/m{sup 3} for a commercial KRB transport gasifier. This heating value is about 80% of the minimum required for firing a gas turbine. Removing 50% of the carbon dioxide from the syngas would increase the heating value to 4583 kJ/m{sup 3}, i.e., to about 110% of the minimum requirement, and 95% removal would provide a heating value of 7080 kJ/m{sup 3}. Supplemental firing of natural gas would also allow the integrated gasification combined cycle (IGCC) technology to be utilized without having to remove CO{sub 2}. If removal of all nitrogen from the input gas streams such as the coal transport air were

  17. JV TASK 45-MERCURY CONTROL TECHNOLOGIES FOR ELECTRIC UTILITIES BURNING LIGNITE COAL, PHASE I BENCH-AND PILOT-SCALE TESTING

    Energy Technology Data Exchange (ETDEWEB)

    John H. Pavlish; Michael J. Holmes; Steven A. Benson; Charlene R. Crocker; Edwin S. Olson; Kevin C. Galbreath; Ye Zhuang; Brandon M. Pavlish

    2003-10-01

    -based activated (800 C, 1472 F) carbons required a shorter (15-minute) conditioning period in the simulated lignite flue gas and captured gaseous mercury more effectively than those activated at 750 C (1382 F). Subsequent tests with higher acid gas concentrations including 50 ppm HCl showed no early mercury breakthrough for either the activated (750 C, 1382 F) Bienfait carbon or the DARCO FGD. Although these high acid gas tests yielded better mercury capture initially, significant breakthrough of mercury ultimately occurred sooner than during the simulated lignite flue gas tests. The steam-activated char, provided by Luscar Ltd., and DARCO FGD, provided by NORIT Americas, were evaluated for mercury removal potential in a 580 MJ/hr (550,000-Btu/hr) pilot-scale coal combustion system equipped with four particulate control devices: (1) an electrostatic precipitator (ESP), (2) a fabric filter (FF), (3) the Advanced Hybrid{trademark} filter, and (4) an ESP and FF in series, an EPRI-patented TOXECON{trademark} technology. The Ontario Hydro method and continuous mercury monitors were used to measure mercury species concentrations at the inlet and outlet of the control technology devices with and without sorbent injection. Primarily Hg{sup o} was measured when lignite coals from the Poplar River Plant and Freedom Mine were combusted. The effects of activated Luscar char, DARCO FGD, injection rates, particle size, and gas temperature on mercury removal were evaluated for each of the four particulate control device options. Increasing injection rates and decreasing gas temperatures generally promoted mercury capture in all four control devices. Relative to data reported for bituminous and subbituminous coal combustion flue gases, higher sorbent injection rates were generally required for the lignite coal to effectively remove mercury. Documented results in this report provide the impacts of these and other parameters and provide the inputs needed to direct Phase II of the project.

  18. Superhydrophobic analyte concentration utilizing colloid-pillar array SERS substrates.

    Science.gov (United States)

    Wallace, Ryan A; Charlton, Jennifer J; Kirchner, Teresa B; Lavrik, Nickolay V; Datskos, Panos G; Sepaniak, Michael J

    2014-12-02

    The ability to detect a few molecules present in a large sample is of great interest for the detection of trace components in both medicinal and environmental samples. Surface enhanced Raman spectroscopy (SERS) is a technique that can be utilized to detect molecules at very low absolute numbers. However, detection at trace concentration levels in real samples requires properly designed delivery and detection systems. The following work involves superhydrophobic surfaces that have as a framework deterministic or stochastic silicon pillar arrays formed by lithographic or metal dewetting protocols, respectively. In order to generate the necessary plasmonic substrate for SERS detection, simple and flow stable Ag colloid was added to the functionalized pillar array system via soaking. Native pillars and pillars with hydrophobic modification are used. The pillars provide a means to concentrate analyte via superhydrophobic droplet evaporation effects. A ≥ 100-fold concentration of analyte was estimated, with a limit of detection of 2.9 × 10(-12) M for mitoxantrone dihydrochloride. Additionally, analytes were delivered to the surface via a multiplex approach in order to demonstrate an ability to control droplet size and placement for scaled-up uses in real world applications. Finally, a concentration process involving transport and sequestration based on surface treatment selective wicking is demonstrated.

  19. PFBC development for lignite-fired CC power plants

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, F.; Meier, H.J.; Smuda, J.V.; Stuhlmueller, F. [VEAG Vereinigte Energiewerke AG (Germany)

    1994-12-31

    A power station design based on pressurised combustion in a circulating fluid-bed is used to illustrate the principle, layout and potential of a lignite-fired combined power station. The fundamental reasons for concentrating on the circulating pressurised fluid-bed consist in its improved emission values, the possibility of separating heat source and heat sink, and better operating performance (part-load). This design has been developed as part of a feasibility study supported by the Federal Ministry for Research and Tehcnology. The paper describes the design of the power plant components. Combustion trials carried out at the pilot plant in Friedrichsfield are reported and the cost-effectiveness of the innovatory design discussed. 10 figs.

  20. Fabrication of Pillar Shaped Electrode Arrays for Artificial Retinal Implants

    Directory of Open Access Journals (Sweden)

    Sung June Kim

    2008-09-01

    Full Text Available Polyimide has been widely applied to neural prosthetic devices, such as the retinal implants, due to its well-known biocompatibility and ability to be micropatterned. However, planar films of polyimide that are typically employed show a limited ability in reducing the distance between electrodes and targeting cell layers, which limits site resolution for effective multi-channel stimulation. In this paper, we report a newly designed device with a pillar structure that more effectively interfaces with the target. Electrode arrays were successfully fabricated and safely implanted inside the rabbit eye in suprachoroidal space. Optical Coherence Tomography (OCT showed well-preserved pillar structures of the electrode without damage. Bipolar stimulation was applied through paired sites (6:1 and the neural responses were successfully recorded from several regions in the visual cortex. Electrically evoked cortical potential by the pillar electrode array stimulation were compared to visual evoked potential under full-field light stimulation.

  1. Interaction of mining activities and aquatic environment: A review from Greek mine sites.

    Science.gov (United States)

    Vasileiou, Eleni; Kallioras, Andreas

    2016-04-01

    In Greece a significant amount of mineral and ore deposits have been recorded accompanied by large industrial interest and a long mining history. Today many active and/or abandoned mine sites are scattered within the country; while mining activities take place in different sites for exploiting various deposits (clay, limestone, slate, gypsum, kaolin, mixed sulphide ores (lead, zinc, olivine, pozzolan, quartz lignite, nickel, magnesite, aluminum, bauxite, gold, marbles etc). The most prominent recent ones are: (i) the lignite exploitation that is extended in the area of Ptolemais (Western Macedonia) and Megalopolis (Central Peloponnese); and (ii) the major bauxite deposits located in central Greece within the Parnassos-Ghiona geotectonic zone and on Euboea Island. In the latter area, significant ores of magnesite were exploited and mixed sulphide ores. Centuries of intensive mining exploitation and metallurgical treatment of lead-silver deposits in Greece, have also resulted in significant abandoned sites, such as the one in Lavrion. Mining activities in Lavrio, were initiated in ancient times and continued until the 1980s, resulting in the production of significant waste stockpiles deposited in the area, crucial for the local water resources. Ιn many mining sites, environmental pressures are also recorded after the mine closure to the aquatic environment, as the surface waters flow through waste dump areas and contaminated soils. This paper aims to the geospatial visualization of the mining activities in Greece, in connection to their negative (surface- and/or ground-water pollution; overpumping due to extensive dewatering practices) or positive (enhanced groundwater recharge; pit lakes, improvement of water budget in the catchment scale) impacts on local water resources.

  2. Nonisothermal Thermogravimetric Analysis of Thai Lignite with High CaO Content

    Science.gov (United States)

    Pintana, Pakamon

    2013-01-01

    Thermal behaviors and combustion kinetics of Thai lignite with different SO3-free CaO contents were investigated. Nonisothermal thermogravimetric method was carried out under oxygen environment at heating rates of 10, 30, and 50°C min−1 from ambient up to 1300°C. Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS) methods were adopted to estimate the apparent activation energy (E) for the thermal decomposition of these coals. Different thermal degradation behaviors were observed in lignites with low (14%) and high (42%) CaO content. Activation energy of the lignite combustion was found to vary with the conversion fraction. In comparison with the KAS method, higher E values were obtained by the FWO method for all conversions considered. High CaO lignite was observed to have higher activation energy than the low CaO coal. PMID:24250259

  3. Environmental Assessment for Lignite Fuel Enhancement Project, Coal Creek Station, Great River Energy, Underwood, North Dakota

    Energy Technology Data Exchange (ETDEWEB)

    N/A

    2004-01-16

    The US Department of Energy (DOE) has prepared this EA to assess the environmental impacts of the commercial application of lignite fuel enhancement. The proposed demonstration project would be implemented at Great River Energy's Coal Creek Station near Underwood, North Dakota. The proposed project would demonstrate a technology to increase the heating value of lignite and other high-moisture coals by reducing the moisture in the fuels. Waste heat that would normally be sent to the cooling towers would be used to drive off a percentage of the moisture contained within the lignite. Application of this technology would be expected to boost power-generating efficiencies, provide economic cost savings for lignite and sub-bituminous power plants, and reduce air emissions. The proposed project would be constructed on a previously disturbed site within the Coal Creek Station and no negative impacts would occur in any environmental resource area.

  4. Aluminium - Cobalt-Pillared Clay for Dye Filtration Membrane

    Science.gov (United States)

    Darmawan, A.; Widiarsih

    2018-04-01

    The manufacture of membrane support from cobalt aluminium pillared clay has been conducted. This research was conducted by mixing a clay suspension with pillared solution prepared from the mixture of Co(NO3)2.6H2O and AlCl3.6H2O. The molar ratio between Al and Co was 75:25 and the ratio of [OH-]/[metal] was 2. The clay suspension was stirred for 24 hours at room temperature, filtered and dried. The dried clay was then calcined at 200°C, 300°C and 400°C with a ramp rate of 2°C/min. Aluminium-cobalt-pillared clay was then characterized by XRD and GSA and moulded become a membrane support for subsequent tests on dye filtration. The XRD analysis showed that basal spacing (d 001) value of aluminium cobalt was 19.49 Å, which was higher than the natural clay of 15.08Å however, the basal spacing decreased with increasing calcination temperature. The result of the GSA analysis showed that the pore diameter of the aluminium cobalt pillared clay membrane was almost the same as that of natural clay that were 34.5Å and 34.2Å, respectively. Nevertheless, the pillared clay has a more uniform pore size distribution. The results of methylene blue filtration measurements demonstrated that the membrane filter support could well which shown by a clear filtrate at all concentrations tested. The value of rejection and flux decreased with the increasing concentration of methylene blue. The values of dye rejection and water flux reached 99.89% and 5. 80 x 10-6 kg min-1, respectively but they decreased with increasing concentration of methylene blue. The results of this study indicates that the aluminium-pillared clay cobalt could be used as membrane materials especially for ultrafiltration.

  5. Stability assessment of the stopes and crown pillar of the S’Argentera abandoned mines (Ibiza, Spain) using geomechanical classifications, an empirical approach and numerical analysis focused on a possible tourist exploitation; Evaluación de la estabilidad de las labores y pilar corona en las minas abandonadas de S’Argentera (Ibiza, España) combinando clasificaciones geomecánicas, métodos empíricos y análisis numérico - enfocado a su posible aprovechamiento turístico.

    Energy Technology Data Exchange (ETDEWEB)

    Jordá-Bordehore, L.; Jordá-Bordehore, R.; Durán Valsero, J.J.; Romero-Crespo, P.L.

    2017-09-01

    The argentiferous lead mines of S’Argentera in Ibiza (Balearic Islands, Spain) are some abandoned underground workings from the first decade of the 20th century. The stability of the main stopes and the crown pillar of the mines has been evaluated - part of which is located below the road between Santa Eulalia and San Carles de Peralta. The possibility of allowing public access to the surface of the mining area and setting up a project of a “show mine” on the underground stopes and galleries is analysed. The stability is assessed with an empirical approach using the O index, the scaled span method and a stability graph together with a numerical approach. Results show that the stopes of the mines are globally stable but some lack an adequate safety factor. Therefore some local reinforcements and monitoring are needed. The finite element modelling in two dimensions yields realistic results on the current stope stability and possible rock falls which have already occurred. [Spanish] Las minas de S’Argentera en Ibiza (Islas Baleares, España) son unas labores subterráneas de plomo argentífero abandonadas desde la primera década del siglo XX. Se ha analizado la estabilidad geotécnica de las cámaras y del pilar corona de las minas (sobre parte del cual pasa la carretera entre Santa Eulalia y San Carles de Peralta), dado que se está contemplando en un futuro permitir el acceso a la parte superior del conjunto de minas e iniciar un proyecto de rehabilitación turística de las labores subterráneas. Se ha evaluado la estabilidad combinando un enfoque empírico mediante el índice Q, método gráfico de estabilidad y ancho escalado, y métodos numéricos de elementos finitos para análisis tensodeformacional. El resultado del análisis muestra que las cámaras de las minas son estables pero algunas no poseen un adecuado factor de seguridad. Por lo tanto son necesarios algunos refuerzos y monitoreo puntuales. La modelización tensodeformacional en dos

  6. Communications construction on mining grounds influenced by mining damage. Budownictwo komunikacyjne na terenach objetych szkodami gorniczymi

    Energy Technology Data Exchange (ETDEWEB)

    Rosikon, A

    1979-01-01

    This book considers problems associated with construction of communication lines on grounds influenced by underground coal mining. It is stated that about 50% of coal mined in Poland comes from protective coal pillars. Improving methods of strata control and ground control after underground mining will influence perspectives of mining in protective pillars. The following problems associated with minimizing mining damage are analyzed: types of ground deformation caused by underground mining, continuous and discontinuous deformation, factors which influence formation of subsidence troughs, forecasting ground subsidence according to the Knothe and Budryk theory, horizontal and vertical ground dislocation, coefficients used for description of ground deformation, Kochmanski's theory of continuous deformation, effects of ground subsidence of foundations of buildings and industrial structures, construction of roads, railway tracks and other communication lines on ground influenced by discontinuous deformations caused by coal mining, problems associated with construction of bridges and tunnels, construction of sewage systems, effects of underground mining on maintenance and repair of communication lines and sewage systems. Ways of minimizing discontinuous ground deformation are analyzed.

  7. Steam gasification of Bulmer coal in the presence of lignite ash

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, A.; Furimsky, E.

    1986-01-01

    Steam gasification of blends prepared from Balmer coal and the ash from combustion of Onakawana lignite was performed in a fixed bed reactor. The blends were prepared by co-slurrying followed by drying. In the presence of 20 wt% ash the gasification rate doubled at 830 and 930 C. Direct blending of coal and lignite resulted in an overall increase in carbon conversion at 830 C but had no effect at 930 C. 5 refs.

  8. Characteristics of Mae Moh lignite: Hardgrove grindability index and approximate work index

    OpenAIRE

    Wutthiphong Tara; Chairoj Rattanakawin

    2012-01-01

    The purpose of this research was to preliminarily study the Mae Moh lignite grindability tests emphasizing onHardgrove grindability and approximate work index determination respectively. Firstly, the lignite samples were collected,prepared and analyzed for calorific value, total sulfur content, and proximate analysis. After that the Hardgrove grindabilitytest using ball-race test mill was performed. Knowing the Hardgrove indices, the Bond work indices of some samples wereestimated using the A...

  9. The reduction of sulfate ions in Musashino woody lignite and in acetone-furfural resin

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, T.

    1986-01-01

    By adding a barium chloride solution to sulfur-containing woody lignite kept in water for two years, it has been confirmed that large quantities of sulfate ions are adsorbed by the lignite. Furthermore, spectroscopic measurements have confirmed the reduction of sulfate ions in an acetone-furfural resin prepared with residual sulfuric acid. These experimental results suggest the possibility of reducing sulfate ions in coal in the absence of sulfate bacteria. 2 refs.

  10. Artisanal and small scale mining in India: selected studies and an overview of the issues

    Energy Technology Data Exchange (ETDEWEB)

    Mihir Deb; Garima Tiwari; Kuntala Lahiri-Dutt [University of Delhi, Delhi (India). School of Environmental Studies

    2008-09-15

    In India, mining is one of the main economic activities since time immemorial, giving rise to a long historical tradition of artisanal mining. As modern mining rose during the colonial occupation, artisanal mining activities began to be overlooked and this great tradition became obscure. This invisibility, added with confusion with regard to legally accepted definitions has enhanced the negligence of the artisanal mining sector in India. This study draws attention to the contemporary artisanal mining practices in India - both traditional and non-traditional ones - with regard to four commodities, gold, tin, coal and lignite, and gemstones. It briefly discusses the occurrences of such mining, their salient features and concludes with four specific recommendations. Recommendations primarily deal with the need for creation of a broader information base, delineating a responsible body to deal with this kind of mining, legal reforms leading to definitional changes and finally, the recognition of the poverty alleviation potential of this sector in view of the Millennium Development Goals.

  11. Naturally occurring radioactive materials (NORMs) generated from lignite-fired power plants in Kosovo.

    Science.gov (United States)

    Hasani, F; Shala, F; Xhixha, G; Xhixha, M K; Hodolli, G; Kadiri, S; Bylyku, E; Cfarku, F

    2014-12-01

    The energy production in Kosovo depends primarily on lignite-fired power plants. During coal combustion, huge amounts of fly ash and bottom ash are generated, which may result in enriched natural radionuclides; therefore, these radionuclides need to be investigated to identify the possible processes that may lead to the radiological exposure of workers and the local population. Lignite samples and NORMs of fly ash and bottom ash generated in lignite-fired power plants in Kosovo are analyzed using a gamma-ray spectrometry method for the activity concentration of natural radionuclides. The average activity concentrations of (40)K, (226)Ra and (232)Th in lignite are found to be 36 ± 8 Bq kg(-1), 9 ± 1 Bq kg(-1) and 9 ± 3 Bq kg(-1), respectively. Indications on the occurrence and geochemical behavior of uranium in the lignite matrix are suggested. The activity concentrations of natural radionuclides in fly ash and bottom ash samples are found to be concentrated from 3 to 5 times that of the feeding lignite. The external gamma-ray absorbed dose rate and the activity concentration index are calculated to assess the radiological hazard arising from ash disposal and recycling in the cement industry. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Analysis of the planned post-mining landscape of MIBRAG's open-cast mines with regard to a possible environmental impact of alteration processes in mixed dumps

    International Nuclear Information System (INIS)

    Jolas, P.; Hofmann, B.

    2010-01-01

    There has been an increasing body of knowledge with regard to hydro- and geochemical alteration processes in overburden dumps and their impact on groundwater quality in lignite mining and reclamation operations associated with post-mining landscapes in Germany. The operators of the MIBRAG mines have examined issues regarding alteration processes and how they affect the environment and which opportunities exist to actively influence the dumping process. The objectives were to counteract any possible negative impact of the alteration processes. Special emphasis was on the impact caused by oxidation of sulfur containing minerals. This paper presented an analysis of the situation at United Schleenhain Mine and how it reflects on the work to date for MIBRAG's mines. A future outlook was also presented. Specifically, the paper discussed the development of the United Schleenhain mine and the post-mining landscape. The potential for discharge of substances was also evaluated along with acidification. 1 tab., 5 figs.

  13. Ground fissures in the area of Mavropigi Village (N. Greece): Seismotectonics or mining activity?

    Science.gov (United States)

    Kalogirou, Eleni; Tsapanos, Theodoros; Karakostas, Vassilios; Marinos, Vassilios; Chatzipetros, Alexandros

    2014-12-01

    In the beginning of July 2010, a ground fissure was observed in the field near the village of Mavropigi (Northern Greece) and specifically in its NW side. Later on (early September), a second ground fissure was perceived, close and almost parallel to the first one and very close to the limits of the lignite exploitation mine (by the Public Power Corporation, PPC). It was observed that the village of Mavropigi slides away slowly towards the PPC lignite mine. Geological, seismological, as well as geotechnical survey in the field indicated that the phenomenon is related to the coal mining exploitation in the near vicinity of the village rather than to any seismotectonic activity in the surrounding area.

  14. In situ measurements of Merensky pillar behaviour at Impala Platinum

    CSIR Research Space (South Africa)

    Watson, BP

    2009-12-01

    Full Text Available to stabilize the stoping excavations. This paper describes the in situ measurement, of stress within a Merensky pillar from Impala Platinum. These measurements were used to derive a stress-strain curve that includes pre and post failure behaviour. 2D FLAC...

  15. Charge transport in nanoscale vertical organic semiconductor pillar devices

    NARCIS (Netherlands)

    Wilbers, J.G.E.; Xu, B.; Bobbert, P.A.; de Jong, M.P.; van der Wiel, W.G.

    2017-01-01

    We report charge transport measurements in nanoscale vertical pillar structures incorporating ultrathin layers of the organic semiconductor poly(3-hexylthiophene) (P3HT). P3HT layers with thickness down to 5 nm are gently top-contacted using wedging transfer, yielding highly reproducible, robust

  16. Energy conservation opportunities: audit vis-a-vis mine productivity

    Energy Technology Data Exchange (ETDEWEB)

    Iyer, G.H.

    2009-07-01

    Mining operation, whether opencast or underground, with modern equipment is highly energy intensive, needing energy conservation and management to ensure efficiency, cost effectiveness, and overall productivity. Exhaustible primary energy resources such as coal, lignite, oil, and nuclear fuels are being mined out to meet our energy needs. An attempt has been made in this paper to highlight the energy conservation opportunities, energy audit, the relevant Energy Conservation Act 2001 and certain energy saving measures leading to higher productivity followed by a few case study examples. 3 refs.

  17. Mechanical properties of pillared-graphene nanostructures using molecular dynamics simulations

    International Nuclear Information System (INIS)

    Wang, Chih-Hao; Fang, Te-Hua; Sun, Wei-Li

    2014-01-01

    The deformation behaviour and mechanical properties of three-dimensional (3D) pillared graphene are investigated using molecular dynamics simulations. The Tersoff–Brenner many-body potential model is employed to evaluate the interactions between 3D pillared-graphene carbon atoms and nanotube carbons. The Lennard-Jones potential model is used to compute the interactions between a conical indenter and 3D pillared-graphene carbon atoms. The effects of the size and geometric structure of 3D pillared-graphene are evaluated in terms of the indentation force and contact stiffness. The simulation results for an armchair nanotube of 3D pillared graphene show that the contact stiffness increases with increasing chiral vector of the 3D-pillared graphene. However, the adhesive force sharply decreases with increasing chiral vector of the 3D-pillared graphene. A zigzag nanotube of 3D-pillared graphene exhibits better mechanical properties compared with those of the armchair nanotube. (paper)

  18. Eco-Friendly Magnetic Iron Oxide Pillared Montmorillonite for Advanced Catalytic Degradation of Dichlorophenol

    Science.gov (United States)

    Eco-friendly pillared montmorillonites, in which the pillars consist of iron oxide are expected to have interesting and unusual magnetic properties that are applicable for environmental decontamination. Completely “green” and effective composite was synthesized using mild reactio...

  19. Validation of a FBC model for co-firing of hazelnut shell with lignite against experimental data

    Energy Technology Data Exchange (ETDEWEB)

    Kulah, Gorkem [Middle East Technical University, Department of Chemical Engineering, 06531 Ankara (Turkey)

    2010-07-15

    Performance of a comprehensive system model extended for modelling of co-firing of lignite and biomass was assessed by applying it to METU 0.3 MW{sub t} Atmospheric Bubbling Fluidized Bed Combustor co-firing lignite with hazelnut shell and validating its predictions against on-line temperature and concentration measurements of O{sub 2}, CO{sub 2}, CO, SO{sub 2} and NO along the same test rig fired with lignite only, lignite with limestone addition and lignite with biomass and limestone addition. The system model accounts for hydrodynamics; volatiles release and combustion, char combustion, particle size distribution for lignite and biomass; entrainment; elutriation; sulfur retention and NO formation and reduction, and is based on conservation equations for energy and chemical species. Special attention was paid to different devolatilization characteristics of lignite and biomass. A volatiles release model based on a particle movement model and a devolatilization kinetic model were incorporated into the system model separately for both fuels. Kinetic parameters for devolatilization were determined via thermogravimetric analysis. Predicted and measured temperatures and concentrations of gaseous species along the combustor were found to be in good agreement. Introduction of biomass to lignite was found to decrease SO{sub 2} emissions but did not affect NO emissions significantly. The system model proposed in this study proves to be a useful tool in qualitatively and quantitatively simulating the processes taking place in a bubbling fluidized bed combustor burning lignite with biomass. (author)

  20. A study relating to the conceptual design and cost estimates of the Saskatchewan Power Corporation lignite beneficiation process

    Energy Technology Data Exchange (ETDEWEB)

    Granatstein, D L; Champagne, P J; Szladow, A J

    1982-06-01

    The purpose is to provide technology for upgrading lignite to a cleaner fuel that is capable of improving utility plant operation and is more acceptable to the non-utility sector. Beneficiated lignite can provide a middle alternative between low-grade and high-grade fuels. The results for phase IV include a conceptual design for a lignite beneficiation plant and a marketing study for the product. The beneficiated lignite is cheaper to transport, easier to handle, cleaner, allows better plant operation with higher availability, reduced slagging and fouling, reduced sulphur, and lower operating and maintenance costs. 8 refs., 6 figs., 7 tabs.

  1. Mining of the 94 East faces, Tau Tona

    CSIR Research Space (South Africa)

    Spottiswoode, SM

    2001-12-01

    Full Text Available A CSIR team visited the 94E1 panels mining the Carbon Leader Reef in the north-east corner of Tau Tona shaft pillar on the 14th December to study the damage due to a rockburst and to recommend any steps that might reduce the potential for further...

  2. A statistical physics consideration about the strength of small size metallic glass pillars

    NARCIS (Netherlands)

    Chen, Changqiang; Pei, Yutao; De Hosson, Jeff Th. M.; Skrotzki, W; Oertel, CG; Biermann, H; Heilmaier, M

    2010-01-01

    We have fabricated micro-/nano-pillars of a Zr-based metallic glass, Zr(50)Ti(16.5)Cu(15)Ni(18.5), with pillar tip diameters ranging from similar to 750 nm to similar to 110 nm. These pillars were mechanically tested quantitatively in-situ in a Transmission Electron Microscope (TEM). Due to a slight

  3. Determine the need to research the time-related stability decay of bord and pillar systems

    CSIR Research Space (South Africa)

    Oberholzer, JW

    1997-07-01

    Full Text Available in decisions regarding research work that could be conducted to investigate the time related decay of bord and pillar workings. As the working consist of pillars of varying shapes and sizes the study concentrated mainly on the aspects of pillar decay...

  4. Naturally occurring radioactive materials (NORMs) generated from lignite-fired power plants in Kosovo

    International Nuclear Information System (INIS)

    Hasani, F.; Shala, F.; Xhixha, G.; Xhixha, M.K.; Hodolli, G.; Kadiri, S.; Bylyku, E.; Cfarku, F.

    2014-01-01

    The energy production in Kosovo depends primarily on lignite-fired power plants. During coal combustion, huge amounts of fly ash and bottom ash are generated, which may result in enriched natural radionuclides; therefore, these radionuclides need to be investigated to identify the possible processes that may lead to the radiological exposure of workers and the local population. Lignite samples and NORMs of fly ash and bottom ash generated in lignite-fired power plants in Kosovo are analyzed using a gamma-ray spectrometry method for the activity concentration of natural radionuclides. The average activity concentrations of 40 K, 226 Ra and 232 Th in lignite are found to be 36 ± 8 Bq kg −1 , 9 ± 1 Bq kg −1 and 9 ± 3 Bq kg −1 , respectively. Indications on the occurrence and geochemical behavior of uranium in the lignite matrix are suggested. The activity concentrations of natural radionuclides in fly ash and bottom ash samples are found to be concentrated from 3 to 5 times that of the feeding lignite. The external gamma-ray absorbed dose rate and the activity concentration index are calculated to assess the radiological hazard arising from ash disposal and recycling in the cement industry. - Highlights: • NORMs in lignite combustion residues from CFPPs are studied. • Th/U indicates either low U uptake from host rocks and/or high leaching from peat. • The concentration factor of NORMs in fly and bottom ash samples are 3–5 times. • No 226 Ra enrichment is observed in fly ash while a depletion in bottom ash. • The reuse of fly ash in cement industry poses no significant radiological issue

  5. Dust precipitation nuisance in the Rhine lignite basin. Situation analysis, legal assessment and the use of compost recycling for emission-protection purposes; Die Staubniederschlagsbelastungen im Rheinischen Braunkohlenrevier. Situationsanalyse, rechtliche Bewertung und Verwertung von Kompost zu Immissionsschutzzwecken

    Energy Technology Data Exchange (ETDEWEB)

    Asenbaum, P. [Bergamt Dueren (Germany)

    2004-03-01

    The paper describes the problem of dust precipitation in the Rhine lignite basin and presents a legal, scientific and technical assessment of how composting can be used for emission protection purposes, along with supporting measures such as the replanting of opencast mining sites. Also examines the benefits, and possible risks, associated with waste recycling projects of this kind. The results of the investigations show that compost recycling for emission-protection purposes can be used to support the emission-protection measures previously deployed at opencast mines in the Rhine lignite basin, including the grassing-over of former mine sites. Such measures are now considered to be technically feasible, environmentally compatible and lawful, and indeed are considered necessary in some circumstances. (orig.) [German] Die Arbeit beschreibt die Staubniederschlagsbelastungen im Rheinischen Braunkohlenrevier und bewertet in diesem Zusammenhang den Einsatz von Kompost zu Immissionsschutzzwecken einschliesslich einer unterstuetzenden Begruenung in den Tagebauen in rechtlicher sowie naturwissenschaftlich-technischer Hinsicht. Darueber hinaus wird die Nuetzlichkeit und Schadlosigkeit dieser Abfallverwertungsmassnahmen beurteilt. Nach den Ergebnissen dieser Arbeit ist eine Kompostverwertung zu Immissionsschutzzwecken zur Ergaenzung des bisherigen Immissionsschutzsystems in den Tagebauen des Rheinischen Braunkohlenreviers einschliesslich einer unterstuetzenden Begruenung technisch moeglich, umweltvertraeglich und rechtlich zulaessig sowie unter bestimmten Voraussetzungen erforderlich. (orig.)

  6. Mineralogy and microstructure of sintered lignite coal fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Marina Ilic; Christopher Cheeseman; Christopher Sollars; Jonathan Knight [Faculty of Technology and Metallurgy, Belgrade (Yugoslavia)

    2003-02-01

    Lignite coal fly ash from the 'Nikola Tesla' power plant in Yugoslavia has been characterised, milled, compacted and sintered to form monolithic ceramic materials. The effect of firing at temperatures between 1130 and 1190{sup o}C on the density, water accessible porosity, mineralogy and microstructure of sintered samples is reported. This class C fly ash has an initial average particle size of 82 {mu}m and contains siliceous glass together with the crystalline phases quartz, anorthite, gehlenite, hematite and mullite. Milling the ash to an average particle size of 5.6 m, compacting and firing at 1170{sup o}C for 1 h produces materials with densities similar to clay-based ceramics that exhibit low water absorption. Sintering reduces the amount of glass, quartz, gehlenite and anhydrite, but increases formation of anorthite, mullite, hematite and cristobalite. SEM confirms the formation of a dense ceramic at 1170{sup o}C and indicates that pyroplastic effects cause pore formation and bloating at 1190{sup o}C. 23 refs., 6 figs., 2 tabs.

  7. Sulfurisation of lipids in a marine-influenced lignite

    Energy Technology Data Exchange (ETDEWEB)

    Sandison, C.M.; Alexander, R.; Kagi, R.I.; Boreham, C.J. [Curtin University of Technology, Perth, WA (Australia)

    2002-07-01

    Compelling evidence is presented for the process of lipid sulfurisation in humic coal-forming environments. The production of reduced inorganic sulfides by sulfate-reducing bacteria during a marine transgression, which occurred during early diagenesis, enabled the selective sequestration of functionalised lipids in the polar and asphaltene fractions from the Eocene, marine-influenced Heartbreak Ridge lignite deposit in southeast Western Australia. Nickel boride desulfurisation experiments conducted on these fractions released small but significant quantities of sulfur-bound hydrocarbons. These comprised mostly higher plant triterpanes, C-29 steranes and extended 17beta(H),21beta(H)-hopanes, linked by one sulfur atom at, or close to, functionalised sites in the original natural product precursors. These sulfurised lipids come from the same carbon sources as the free hydrocarbon lipids, except for the sulfurised extended hopanoids, which may be partially derived from a different bacterial source. These results indicate that the selectivity and nature of steroid and hopanoid vulcanisation in coal-forming mires is similar to that observed in other sedimentary environments. However, the diversity of higher plant triterpanes that can be sulfurised in marine transgressed coals is greater than that reported in immature terrestrial coals. This preservation mechanism explains the formation of the structurally related biomarkers in more mature sulfur-rich humic coals.

  8. Computer simulations of discharges from a lignite power plant complex

    International Nuclear Information System (INIS)

    Koukouliou, V.; Horyna, J.; Perez-Sanchez, D.

    2008-01-01

    This paper describes work carried out within the IAEA EMRAS program NORM working group to test the predictions of three computer models against measured radionuclide concentrations resulting from discharges from a lignite power plant complex. This complex consists of two power plants with a total of five discharge stacks, situated approximately 2-5 kilometres from a city of approximately 10,000 inhabitants. Monthly measurements of mean wind speed and direction, dust loading, and 238 U activities in fallout samples, as well as mean annual values of 232 Th activity in the nearest city sampling sites were available for the study. The models used in the study were Pc-CREAM (a detailed impact assessment model), and COMPLY and CROM (screening models). In applying the models to this scenario it was noted that the meteorological data provided was not ideal for testing, and that a number of assumptions had to be made, particularly for the simpler models. However, taking the gaps and uncertainties in the data into account, the model predictions from PC-CREAM were generally in good agreement with the measured data, and the results from different models were also generally consistent with each other. However, the COMPLY predictions were generally lower than those from PC-CREAM. This is of concern, as the aim of a screening model (COMPLY) is to provide conservative estimates of contaminant concentrations. Further investigation of this problem is required. The general implications of the results for further model development are discussed. (author)

  9. Product analysis of catalytic multi-stage hydropyrolysis of lignite

    Energy Technology Data Exchange (ETDEWEB)

    Wen Li; Na Wang; Baoqing Li [Chinese Academy of Science, Taiyuan (China). State Key Lab of Coal Conversion, Institute of Coal Chemistry

    2003-03-01

    A lignite added with 0.2% MoS{sub 2} as catalyst was pyrolyzed under H{sub 2} using multi-stage heating method (MHyPy) which means holding a suitable time near the peak temperature. The product distribution and detailed analysis of products were performed. The results show that the tar yield increased to 63.9% during MHyPy compared with that of 51.8% in traditional hydropyrolysis (HyPy), while the gas yield decreased to a half. This suggests the effective utilization of hydrogen during MHyPy. The light aromatics in the tar from MHyPy increased remarkably 42, 37.8 and 115.4% for BTX, PCX and naphthalenes, respectively. Biphenyls were also observed in the tar from MHyPy, which indicated the effective hydrogenation occurs during catalytic MHyPy. The rich pore structure of the char from MHyPy hints its high reactivity in the subsequent conversion process such as gasification and combustion. 15 refs., 7 figs., 2 tabs.

  10. Growth response of microorganisms to different molecular fractions of lignite

    Energy Technology Data Exchange (ETDEWEB)

    Polman, J.K.; Breckenridge, C.R.; Dugan, P.R.; Quigley, D.R.

    1990-01-01

    Our research is primarily concerned with isolating and characterizing microbes which are able to dissimilate coal and convert it to other useful chemicals. This quarter, general growth responses of microorganisms cultivated in the presence of different molecular weight fractions of lignite coal were examined. Aerobic and anaerobic environmental samples from a variety of ecological niches were used as inocula. Growth of the microorganisms in these samples on the following types of media was tested: COAL medium, containing alkali-solubilized whole coal; THFI medium, containing the alkali-solubilized, tetrahydrofuran-insoluble, macromolecular portion of whole coal; THFS medium, containing the THF-soluble, low molecular weight portion of whole coal; and CON medium, void of any coal constituent. Overall results indicated that the presence of the THF-soluble, low molecular weight coal fraction enhanced the growth yield and the variety of aerobic microorganisms compared to the other coal fractions or the control medium. Conversely, anaerobic microbes grew best on media which contained the macromolecular fraction. 12 refs., 5 tabs.

  11. Oxidative desulfurization of Cayirhan lignites by permanganate solution

    Energy Technology Data Exchange (ETDEWEB)

    Guru, M.; Tuzun, F.N.; Murathan, A.S.; Asan, A.; Kiyak, T. [Gazi University, Ankara (Turkey). Dept. for Chemical Engineering

    2008-07-01

    Unless important developments record new and renewable energy sources, the role of fossil fuels as an energy resource goes on. It is possible to detect sulfur, heavy metals, and tracer elements such as arsenic and selenium by decreasing calorific value of coals. Sulfur oxides, which are the main pollutants in atmosphere, are irritative to humans and plants, and erosion occurs on buildings. Although there are high lignite reservoirs, high sulfur content limits the efficient use of them. In this research, it is aimed to convert combustible sulfur in coal to non-combustible sulfur form in the ash by oxidizing it with permanganate solution. During this research, the effect of two different parameters of potassium permanganate concentration, processing time, and mean particle size were investigated at constant room temperature and shaking rate. The conversion of combustible sulfur to non-combustible sulfur form was achieved optimally with 0.14 M potassium permanganate solution, 0.1 mm mean particle size at 16 h of treatment time, and the combustible sulfur amount was decreased by 46.37% compared to undoped conditions.

  12. Light Rare Earth Elements enrichment in an acidic mine lake (Lusatia, Germany)

    International Nuclear Information System (INIS)

    Bozau, Elke; Leblanc, Marc; Seidel, Jean Luc; Staerk, Hans-Joachim

    2004-01-01

    The distribution of Rare Earth Elements (REE) was investigated in the acidic waters (lake and groundwater) of a lignite mining district (Germany). The Fe- and SO 4 -rich lake water (pH 2.7) displays high REE contents (e.g. La∼70 μg/l, Ce∼160 μg/l) and an enrichment of light REE (LREE) in the NASC normalised pattern. Considering the hydrodynamic model and geochemical data, the lake water composition may be calculated as a mixture of inflowing Quaternary and mining dump groundwaters. The groundwater of the dump aquifer is LREE enriched. Nevertheless, the leachates of dump sediments generally have low REE contents and display flat NASC normalised patterns. However, geochemical differences and REE pattern in undisturbed lignite (LREE enriched pattern and low water soluble REE contents) and the weathered lignite of the dumps (flat REE pattern and high water soluble REE contents) suggest that lignite is probably the main REE source rock for the lake water

  13. Effects of lignite application on ammonia and nitrous oxide emissions from cattle pens

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jianlei, E-mail: su@unimelb.edu.au [Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC 3010 (Australia); Bai, Mei [Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC 3010 (Australia); Shen, Jianlin [Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125 (China); Griffith, David W.T. [Department of Chemistry, University of Wollongong, NSW 2522 (Australia); Denmead, Owen T. [Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC 3010 (Australia); Hill, Julian [Ternes Agricultural Consulting Pty Ltd, Upwey, VIC 3158 (Australia); Lam, Shu Kee; Mosier, Arvin R. [Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC 3010 (Australia); Chen, Deli, E-mail: delichen@unimelb.edu.au [Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC 3010 (Australia)

    2016-09-15

    Beef cattle feedlots are a major source of ammonia (NH{sub 3}) emissions from livestock industries. We investigated the effects of lignite surface applications on NH{sub 3} and nitrous oxide (N{sub 2}O) emissions from beef cattle feedlot pens. Two rates of lignite, 3 and 6 kg m{sup −2}, were tested in the treatment pen. No lignite was applied in the control pen. Twenty-four Black Angus steers were fed identical commercial rations in each pen. We measured NH{sub 3} and N{sub 2}O concentrations continuously from 4th Sep to 13th Nov 2014 using Quantum Cascade Laser (QCL) NH{sub 3} analysers and a closed-path Fourier Transform Infrared Spectroscopy analyser (CP-FTIR) in conjunction with the integrated horizontal flux method to calculate NH{sub 3} and N{sub 2}O fluxes. During the feeding period, 16 and 26% of the excreted nitrogen (N) (240 g N head{sup −1} day{sup −1}) was lost via NH{sub 3} volatilization from the control pen, while lignite application decreased NH{sub 3} volatilization to 12 and 18% of the excreted N, for Phase 1 and Phase 2, respectively. Compared to the control pen, lignite application decreased NH{sub 3} emissions by approximately 30%. Nitrous oxide emissions from the cattle pens were small, 0.10 and 0.14 g N{sub 2}O-N head{sup −1} day{sup −1} (< 0.1% of excreted N) for the control pen, for Phase 1 and Phase 2, respectively. Lignite application increased direct N{sub 2}O emissions by 40 and 57%, to 0.14 and 0.22 g N{sub 2}O-N head{sup −1} day{sup −1}, for Phase 1 and Phase 2, respectively. The increase in N{sub 2}O emissions resulting from lignite application was counteracted by the lower indirect N{sub 2}O emission due to decreased NH{sub 3} volatilization. Using 1% as a default emission factor of deposited NH{sub 3} for indirect N{sub 2}O emissions, the application of lignite decreased total N{sub 2}O emissions. - Graphical abstract: Lignite application substantially decreased NH{sub 3} emissions from cattle feedlots and increased

  14. Supporting Solar Physics Research via Data Mining

    Science.gov (United States)

    Angryk, Rafal; Banda, J.; Schuh, M.; Ganesan Pillai, K.; Tosun, H.; Martens, P.

    2012-05-01

    In this talk we will briefly introduce three pillars of data mining (i.e. frequent patterns discovery, classification, and clustering), and discuss some possible applications of known data mining techniques which can directly benefit solar physics research. In particular, we plan to demonstrate applicability of frequent patterns discovery methods for the verification of hypotheses about co-occurrence (in space and time) of filaments and sigmoids. We will also show how classification/machine learning algorithms can be utilized to verify human-created software modules to discover individual types of solar phenomena. Finally, we will discuss applicability of clustering techniques to image data processing.

  15. Changes of chemical properties of humic acids from crude and fungal transformed lignite

    Energy Technology Data Exchange (ETDEWEB)

    LianHua Dong; Quan Yuan; HongLi Yuan [China Agricultural University, Beijing (China). College of Biological Science

    2006-12-15

    The development of biological processes for fossil energy utilization has received increasing attention in recent years. There are abundance of lignite resources in China and the lignite, a low-grade coal, can be transformed by a Penicillium sp. After fungal transformation, the contents of humic acid and water-soluble humic material increased from 38.6% to 55.1%, and from less than 4.0% to 28.2%, respectively. The differences in chemical properties of crude lignite humic acid (aHA), fungal transformed lignite humic acid (bHA) and water-soluble humic material from fungal transformed lignite (WS) were studied. Elemental analysis and size exclusion chromatography showed that the N content of bHA increased by 47.36% compared with aHA, and the molecular mass of bHA was smaller than aHA. And the WS with the smallest molecular mass contained most content of N. The {sup 13}C NMR and FT-IR spectra of aHA and bHA showed that aHA contained more aromatic structure than bHA. 44 refs., 3 figs., 2 tabs.

  16. A lignite-geothermal hybrid power and hydrogen production plant for green cities and sustainable buildings

    Energy Technology Data Exchange (ETDEWEB)

    Kilkis, B. [Baskent University, Ankara (Turkey). Dept. of Mechanical Engineering

    2011-02-15

    Turkey is rich in both geothermal energy and lignite reserves, which in many cases, are co-located. This condition makes it feasible to utilize both lignite and geothermal energy in a hybrid form for combined power heat, and cold generation, which may lead to optimally energy and exergy efficient, environmentally benign, and economically sound applications. This paper presents a novel concept of hybrid lignite-geothermal plant for a district energy system and hydrogen production facility in Aydin with special emphasis on high performance, green buildings and green districts. In this concept, lignite is first introduced to a partially fluidized-bed gasifier and then to a fluidized-bed gas cleaning unit, which produces synthetic gas and finally hydrogen. The by-products, namely char and ash are used in a fluidized-bed combustor to produce power. Waste heat from all these steps are utilized in a district heating system along with heat received from geothermal production wells after power is generated there. H{sub 2}S gas obtained from the separator system is coupled with hydrogen production process at the lignite plant. Absorption cooling systems and thermal storage tanks complement the hybrid system for the tri-generation district energy system. On the demand side, the new, green OSTIM OSB administration building in Ankara is exemplified for greener, low-exergy buildings that will compound the environmental benefits.

  17. Aespoe Pillar Stability Experiment. Acoustic emission and ultrasonic monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Haycox, Jon; Pettitt, Will; Young, R. Paul [Applied Seismology Consultants Ltd., Shrewsbury (United Kingdom)

    2005-12-15

    This report describes the results from acoustic emission (AE) and ultrasonic monitoring of the Aespoe Pillar Stability Experiment (APSE) at SKB's Hard Rock Laboratory (HRL), Sweden. The APSE is being undertaken to demonstrate the current capability to predict spalling in a fractured rock mass using numerical modelling techniques, and to demonstrate the effect of backfill and confining pressure on the propagation of micro-cracks in rock adjacent to deposition holes within a repository. An ultrasonic acquisition system has provided acoustic emission and ultrasonic survey monitoring throughout the various phases of the experiment. Results from the entire data set are provided with this document so that they can be effectively compared to several numerical modelling studies, and to mechanical and thermal measurements conducted around the pillar volume, in an 'integrated analysis' performed by SKB staff. This document provides an in-depth summary of the AE and ultrasonic survey results for future reference. The pillar has been produced by excavating two 1.8 m diameter deposition holes 1 m apart. These were bored in 0.8 m steps using a Tunnel Boring Machine specially adapted for vertical drilling. The first deposition hole was drilled in December 2003. Preceding this a period of background monitoring was performed so as to obtain a datum for the results. The hole was then confined to 0.7 MPa internal over pressure using a specially designed water-filled bladder. The second deposition hole was excavated in March 2004. Heating of the pillar was performed over a two month period between ending in July 2004, when the confined deposition hole was slowly depressurised. Immediately after depressurisation the pillar was allowed to cool with cessation of monitoring occurring a month later. A total of 36,676 AE triggers were recorded over the reporting period between 13th October 2003 and 14th July 2004. Of these 15,198 have produced AE locations. The AE data set

  18. Aespoe Pillar Stability Experiment. Acoustic emission and ultrasonic monitoring

    International Nuclear Information System (INIS)

    Haycox, Jon; Pettitt, Will; Young, R. Paul

    2005-11-01

    This report describes the results from acoustic emission (AE) and ultrasonic monitoring of the Aespoe Pillar Stability Experiment (APSE) at SKB's Hard Rock Laboratory (HRL), Sweden. The APSE is being undertaken to demonstrate the current capability to predict spalling in a fractured rock mass using numerical modelling techniques, and to demonstrate the effect of backfill and confining pressure on the propagation of micro-cracks in rock adjacent to deposition holes within a repository. An ultrasonic acquisition system has provided acoustic emission and ultrasonic survey monitoring throughout the various phases of the experiment. Results from the entire data set are provided with this document so that they can be effectively compared to several numerical modelling studies, and to mechanical and thermal measurements conducted around the pillar volume, in an 'integrated analysis' performed by SKB staff. This document provides an in-depth summary of the AE and ultrasonic survey results for future reference. The pillar has been produced by excavating two 1.8 m diameter deposition holes 1 m apart. These were bored in 0.8 m steps using a Tunnel Boring Machine specially adapted for vertical drilling. The first deposition hole was drilled in December 2003. Preceding this a period of background monitoring was performed so as to obtain a datum for the results. The hole was then confined to 0.7 MPa internal over pressure using a specially designed water-filled bladder. The second deposition hole was excavated in March 2004. Heating of the pillar was performed over a two month period between ending in July 2004, when the confined deposition hole was slowly depressurised. Immediately after depressurisation the pillar was allowed to cool with cessation of monitoring occurring a month later. A total of 36,676 AE triggers were recorded over the reporting period between 13th October 2003 and 14th July 2004. Of these 15,198 have produced AE locations. The AE data set shows an intense

  19. De-acidification of flooded lignite mining lakes by controlled eutrophication: mesocosm experiments

    International Nuclear Information System (INIS)

    Steinberg, C.E.W.; Totsche, O.; Fyson, A.; Brandenburgische Technische Univ. Cottbus; Nixdorf, B.

    2000-01-01

    Mesocosm experiments with Tagebausee water overlying Tagebausee sediment indicate that without continued inflow of groundwater, some acidity will likely be removed (through Fe(OH) 3 precipitation). Alkalinity production can be greatly enhanced through addition of organic wastes containing decomposible organic carbon and nutrients. Once neutral conditions are achieved, they can be maintained without additional acid inputs through sustained C input (through photosynthesis) and enhanced geochemical cycling to maintain nutrient supply (e.g. P). The role of algal and bacterial growth in acidity/alkalinity balance are currently under investigation. (orig.)

  20. Trust Mines

    Science.gov (United States)

    The United States and the Navajo Nation entered into settlement agreements that provide funds to conduct investigations and any needed cleanup at 16 of the 46 priority mines, including six mines in the Northern Abandoned Uranium Mine Region.

  1. Crystallography of Representative MOFs Based on Pillared Cyanonickelate (PICNIC Architecture

    Directory of Open Access Journals (Sweden)

    Winnie Wong-Ng

    2016-09-01

    Full Text Available The pillared layer motif is a commonly used route to porous coordination polymers or metal organic frameworks (MOFs. Materials based on the pillared cyano-bridged architecture, [Ni’(LNi(CN4]n (L = pillar organic ligands, also known as PICNICs, have been shown to be especially diverse where pore size and pore functionality can be varied by the choice of pillar organic ligand. In addition, a number of PICNICs form soft porous structures that show reversible structure transitions during the adsorption and desorption of guests. The structural flexibility in these materials can be affected by relatively minor differences in ligand design, and the physical driving force for variations in host-guest behavior in these materials is still not known. One key to understanding this diversity is a detailed investigation of the crystal structures of both rigid and flexible PICNIC derivatives. This article gives a brief review of flexible MOFs. It also reports the crystal structures of five PICNICS from our laboratories including three 3-D porous frameworks (Ni-Bpene, NI-BpyMe, Ni-BpyNH2, one 2-D layer (Ni-Bpy, and one 1-D chain (Ni-Naph compound. The sorption data of BpyMe for CO2, CH4 and N2 is described. The important role of NH3 (from the solvent of crystallization as blocking ligands which prevent the polymerization of the 1-D chains and 2-D layers to become 3D porous frameworks in the Ni-Bpy and Ni-Naph compounds is also addressed.

  2. Wettability modification of Wender lignite by adsorption of dodecyl poly ethoxylated surfactants with different degree of ethoxylation: A molecular dynamics simulation study.

    Science.gov (United States)

    Zhang, Lei; Li, Bao; Xia, Yangchao; Liu, Shengyu

    2017-09-01

    Lignite is an important and useful fossil fuel in the world and the strong hydrophilicity of it limits its applications. Surfactant adsorption on lignite is an effective way to make it hydrophobic. In this work, aiming to examine the effect of the degree of ethoxylation on the adsorption behavior of dodecyl poly ethoxylated surfactants on lignite and the wettability modification of modified lignite by surfactant adsorption, different combined systems formed by surfactants, water and a model surface of Wender lignite have been studied using molecular dynamics simulation. The adsorption configurations vary with the degree of ethoxylation. At the same adsorption amounts, increasing the degree of ethoxylation can make the adsorption layer more compactness and bring stronger adsorption strength. The results of binding energy and its components show that the adsorption of alkyl polyoxyethylene ethers surfactant on lignite is physically adsorbed rather than electrostatically or chemisorbed. Meanwhile, van der Waals interaction plays a dominant role in the adsorption. The addition of surfactant could reduce the possibility of the interaction between water and lignite. Compared to the original lignite, the interaction between them is weakened after surfactant adsorption in water/surfactant/lignite system, thus strengthening the hydrophobicity of lignite. Similar to the adsorption strength, hydrophobicity of modified lignite increases with the increase of the degree of ethoxylation. The lignite surface properties are changed due to surfactant adsorption by analyzing the compositions of interaction energy and the change of hydrogen bonds. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Allowable pillar to diameter ratio for strategic petroleum reserve caverns.

    Energy Technology Data Exchange (ETDEWEB)

    Ehgartner, Brian L.; Park, Byoung Yoon

    2011-05-01

    This report compiles 3-D finite element analyses performed to evaluate the stability of Strategic Petroleum Reserve (SPR) caverns over multiple leach cycles. When oil is withdrawn from a cavern in salt using freshwater, the cavern enlarges. As a result, the pillar separating caverns in the SPR fields is reduced over time due to usage of the reserve. The enlarged cavern diameters and smaller pillars reduce underground stability. Advances in geomechanics modeling enable the allowable pillar to diameter ratio (P/D) to be defined. Prior to such modeling capabilities, the allowable P/D was established as 1.78 based on some very limited experience in other cavern fields. While appropriate for 1980, the ratio conservatively limits the allowable number of oil drawdowns and hence limits the overall utility and life of the SPR cavern field. Analyses from all four cavern fields are evaluated along with operating experience gained over the past 30 years to define a new P/D for the reserve. A new ratio of 1.0 is recommended. This ratio is applicable only to existing SPR caverns.

  4. Desulfurization of organic sulfur from lignite by an electron transfer process

    Energy Technology Data Exchange (ETDEWEB)

    Demirbas, A. [Selcuk University, Konya (Turkey). Dept. for Chemical Engineering

    2006-10-15

    This study is an attempt to desulfurize organic sulfur from lignite samples with ferrocyanide ion as the electron transferring agent. Effect of temperature, particle size and concentration of ferrocyanide ion on desulfurization from the lignite samples has been investigated. The desulfurization process has been found to be continuous and gradually increases with increase of temperature from 298 to 368 K. The particle size has no significant impact on sulfur removal from the lignite samples. Particle size has no profound impact on the amount of sulfur removal. The desulfurization reaction has been found to be dependent on the concentration of potassium ferrocyanide. Gradual increase in the concentration of potassium ferrocyanide raised the magnitude of desulfurization, but at a higher concentration, the variation is not significant.

  5. Acid leaching of coal: to produce clean fuels from Turkish lignite

    Energy Technology Data Exchange (ETDEWEB)

    Seferinoglu, Meryem [Mineral Research and Exploration Directorate (Turkey)], email: meryem_seferinoglu66@yahoo.com; Duzenli, Derya [Ankara Central Laboratory (Turkey)

    2011-07-01

    With the increasing concerns about the environment, energy producers and governments are looking at developing clean energy sources. However, Turkey has limited clean energy resources and is using low grade coal which has high sulphur content as an alternative energy source. The aim of this paper is to study the possibility of generating clean fuel from Edirne Lignite and to get a better understanding of chemical mechanisms involved in coal leaching with hydrofluoric acid (HF) solutions. Leaching was conducted on Edirne Lignite with HF solution at ambient temperature and the effects of parameters such as reaction time and concentration of acid solutions on the process were evaluated. The optimum conditions were found and it was shown that ash levels can be reduced from 28.9% to 10.5% and the calorific value increased by 500kcal/kg with the HF leaching method. This study demonstrated that the production of clean fuel from high sulphur lignite is possible.

  6. Thermogravimetric investigation of the co-combustion between the pyrolysis oil distillation residue and lignite.

    Science.gov (United States)

    Li, Hao; Xia, Shuqian; Ma, Peisheng

    2016-10-01

    Co-combustion of lignite with distillation residue derived from rice straw pyrolysis oil was investigated by non-isothermal thermogravimetric analysis (TGA). The addition of distillation residue improved the reactivity and combustion efficiency of lignite, such as increasing the weight loss rate at peak temperature and decreasing the burnout temperature and the total burnout. With increasing distillation residue content in the blended fuels, the synergistic interactions between distillation residue and lignite firstly increased and then decreased during co-combustion stage. Results of XRF, FTIR, (13)C NMR and SEM analysis indicated that chemical structure, mineral components and morphology of samples have great influence on the synergistic interactions. The combustion mechanisms and kinetic parameters were calculated by the Coats Redfern model, suggesting that the lowest apparent activation energy (120.19kJ/mol) for the blended fuels was obtained by blending 60wt.% distillation residue during main co-combustion stage. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Naturally Occurring Radionuclides of Ash Produced by Coal Combustion. The Case of the Kardia Mine in Northern Greece

    Science.gov (United States)

    Fotakis, M.; Tsikritzis, L.; Tzimkas, N.; Kolovos, N.; Tsikritzi, R.

    2008-08-01

    West Macedonia Lignite Center (WMLC), located in Northwest Greece, releases into the atmosphere about 21,400 tons/year of fly ash through the stacks of four coal fired plants. The lignite ash contains naturally occurring radionuclides, which are deposited on the WMLC basin. This work investigates the natural radioactivity of twenty six ash samples, laboratory produced from combustion of lignite, which was sampled perpendicularly to the benches of the Kardia mine. The concentrations of radionuclides 40K, 235U, 238U, 226Ra, 228Ra and 232Th, were measured spectroscopically and found round one order of magnitude as high as those of lignite. Subsequently the Radionuclide Partitioning Coefficients of radionuclides were calculated and it was found that they are higher for 232Th, 228Ra and 40K, because the latter have closer affinity with the inorganic matrix of lignite. During combustion up to one third of the naturally occurring radioisotopes escape from the solid phase into the flue gases. With comparison to relative global data, the investigated ash has been found to have relatively high radioactivity, but the emissions of the WMLC radionuclides contribute only 0.03% to the mean annual absorbed dose.

  8. Naturally Occurring Radionuclides of Ash Produced by Coal Combustion. The Case of the Kardia Mine in Northern Greece

    International Nuclear Information System (INIS)

    Fotakis, M.; Tsikritzis, L.; Tzimkas, N.; Kolovos, N.; Tsikritzi, R.

    2008-01-01

    West Macedonia Lignite Center (WMLC), located in Northwest Greece, releases into the atmosphere about 21,400 tons/year of fly ash through the stacks of four coal fired plants. The lignite ash contains naturally occurring radionuclides, which are deposited on the WMLC basin. This work investigates the natural radioactivity of twenty six ash samples, laboratory produced from combustion of lignite, which was sampled perpendicularly to the benches of the Kardia mine. The concentrations of radionuclides 40 K, 235 U, 238 U, 226 Ra, 228 Ra and 232 Th, were measured spectroscopically and found round one order of magnitude as high as those of lignite. Subsequently the Radionuclide Partitioning Coefficients of radionuclides were calculated and it was found that they are higher for 232 Th, 228 Ra and 40 K, because the latter have closer affinity with the inorganic matrix of lignite. During combustion up to one third of the naturally occurring radioisotopes escape from the solid phase into the flue gases. With comparison to relative global data, the investigated ash has been found to have relatively high radioactivity, but the emissions of the WMLC radionuclides contribute only 0.03% to the mean annual absorbed dose

  9. REMOVAL OF TRICHLOROACETIC ACID FROM THE AQUEOUS SOLUTIONS USING NATURAL AND ACTIVATED LIGNITE COALS

    Directory of Open Access Journals (Sweden)

    Hüseyin GÜLENSOY

    1998-02-01

    Full Text Available In these studies, a typical lignite coal found near Istanbul (Yeniköy and its activated products were used to adsorb TCA from aqueous solutions. Particle sizes of coal samples and the concentrations of TCA solutions were chosen as parameters against the fixed amount of adsorbent. The maximum efficiency has been obtained for the coal having (-120 + 150 mesh size fraction activated by heating. As a result, it was shown that these kinds of lignite coals could be used as a good adsorbent. In addition, it was also proved that both the removal and recovery of TCA from some waste waters would easily be possible.

  10. Production of metallurgical cokes from some Turkish lignites using sulphite liquor binders

    Energy Technology Data Exchange (ETDEWEB)

    Yanik, J.; Saglam, M.; Yuksel, M. (Ege University, Izmir (Turkey). Dept. of Chemistry)

    1990-04-01

    Soma and Tuncbilek lignites were briquetted at 80{degree}C under 0-100 MPa, using varying amounts of sulphite liquor binders. The briquettes were then carbonized at 950{degree}C, and the resulting formed cokes were examined. The effects of the type and concentration of binders, and of the briquetting pressure, on the strength and porosity of the formcokes were investigated. As a result of these experiments, optimal briquetting conditions were established. It was also stated that formcokes made from both Turkish lignite samples under optimal briquetting conditions could be used for metallurgical purposes, particularly in non-ferrous metallurgy. 17 refs., 1 fig., 4 tabs.

  11. Underground coal mining - methods, equipment developments and trends

    Energy Technology Data Exchange (ETDEWEB)

    Singhal, R

    1988-12-01

    Underground mines are truly beginning to accept the so-called 'high tech' technology evident in other industries. Automation, remote control and robotics have taken an added significance. Wireless communication, mine-wide equipment health and performance monitoring, and transmission of data from deeper levels to surface is moving towards becoming the norm. There is emphasis on developing and applying continuous mining systems, as well as on modifying cyclical discontinuous methods to continuous systems. Multi-purpose equipment is also being developed. Technology transfer is playing its role - equipment and systems from surface coal mining are being applied to underground mining and vice-versa. At the American Mining Congress Exhibition held in Chicago in April 1988, a variety of equipment for underground mining was displayed including coal face equipment such as shearer loaders, conveyors and powered supports, and equipment for room-and-pillar coal mining. The trend continues to be towards high power machines equipped with a variety of electronics and sensors, safety devices, and alarm systems. Ancillary equipment on display covered a variety of cutting drums, cutting tools, conveying equipment and so on. In room-and-pillar mining, the overall emphasis was on moving away from the cyclical nature of the work. Transportation by shuttle cars must be replaced by continuous transport systems such as conveyors. Experience from Australia has shown that the application of continuous haulage and breaker line supports has permitted a doubling of production from room-and-pillar systems. Production levels of 3,000tpd have already been achieved, and 4,000tpd is considered achievable.

  12. Deformation-driven diffusion and plastic flow in amorphous granular pillars.

    Science.gov (United States)

    Li, Wenbin; Rieser, Jennifer M; Liu, Andrea J; Durian, Douglas J; Li, Ju

    2015-06-01

    We report a combined experimental and simulation study of deformation-induced diffusion in compacted quasi-two-dimensional amorphous granular pillars, in which thermal fluctuations play a negligible role. The pillars, consisting of bidisperse cylindrical acetal plastic particles standing upright on a substrate, are deformed uniaxially and quasistatically by a rigid bar moving at a constant speed. The plastic flow and particle rearrangements in the pillars are characterized by computing the best-fit affine transformation strain and nonaffine displacement associated with each particle between two stages of deformation. The nonaffine displacement exhibits exponential crossover from ballistic to diffusive behavior with respect to the cumulative deviatoric strain, indicating that in athermal granular packings, the cumulative deviatoric strain plays the role of time in thermal systems and drives effective particle diffusion. We further study the size-dependent deformation of the granular pillars by simulation, and find that different-sized pillars follow self-similar shape evolution during deformation. In addition, the yield stress of the pillars increases linearly with pillar size. Formation of transient shear lines in the pillars during deformation becomes more evident as pillar size increases. The width of these elementary shear bands is about twice the diameter of a particle, and does not vary with pillar size.

  13. Process and device for producing a timber gear case for tunnels and mines

    Energy Technology Data Exchange (ETDEWEB)

    Foik, A

    1977-09-08

    A device is described for producing a timber gear case for tunnels and mines. Plank shaped pillars, partly overlapping one another are driven in parallel planes at an angle to the tunnel axis, close together and advancing relative to the face. The pillars are taken through supports erected one after the other in the longitudinal direction of the tunnel, and are supported. The process can be extended by producing a timber gear case to secure any type of underground space. The process produces further mechanisation of tunnelling and mining and also ensures greater safety for the miners.

  14. Lignite utilisation for binding of radionuclides and uranium determination by adsorptive stripping chronopotentiometry

    International Nuclear Information System (INIS)

    Zavodska, L.

    2010-01-01

    This work in its first part deals with non-energetic use of young brown coal - lignite. The goal of the work was to perform a complex physical and chemical characterisation of the Slovak lignite (deposit Cary) which could contribute to rts use in binding of radionuclides in the environment. The characteristics of Slovak lignite were compared to leonardite (Gascoyne, USA) and Czech lignite (the area of Mikulcice). In the samples the residual humidity was determined. as well. as the content of ashes. representation of selected inorganic (As, Ba, Cd, Co, Cr, Cu, Ni, Pb and Zn) as well as organo-elements (C, H, N, 0, S) and crystalline forms of inorganic phase in lignite. The specific surface (BET isotherm) of lignite was determined, representation of total and free humic acids and their cation exchange capacity. The samples underwent al.so gamma-spectrometric analysis ( 40 K, 226 Ra, 228 Ac, 137 Cs and 60 Co). Using the radio-indicator method ( 85 Sr and 137 Cs) the kinetics of sorption of Cs + and Sr + ions in Slovak lignite was studied. The efficiency of sorption for both cations on lignite was evaluated on the basis of constructed sorption isotherms. The sorption of Cs + ions on Slovak lignite is more suitable for the Freundlich type of isotherm, in case of Sr + ions the sorption is better described by Langmuir isotherm. The results of sorption experiments on lignite in comparison with clinoptilolite and montmorillonite K-10 showed a more efficient sorption for Sr Ions. despite the more coarse-grained fraction of this matrix. This finding supports the possibility of lignite application for binding of a quite mobile radiostrontium, which may be applied for construction of radioactive waste repositories or for remediation of contaminated soils. The second part of the work deals with the development and validation of new fast and reliable electrochemical method of uranium determination in natural waters. It is based on physical adsorption of created complex of uranium

  15. Low NOx firing systems for bituminous coal and lignite

    International Nuclear Information System (INIS)

    Knyrim, W.; Scheffknecht, G.

    1997-01-01

    In the case of lignite fluidized boilers the denitrification down to less than 200 mg/m 3 was possible with primary measures on the firing side only. On account of the excellent results achieved with the reconstructed plants the firing systems for the new generation of brown coal fire steam generators with a capacity of 800 MW and more is designed in a similar way. For bituminous coal fire steam generators the primary measures on the firing side are nor sufficient to keep the German NO x emission limit. Therefore these units had to be retrofitted with a SCR-DENOX plant. The experience with the new firing system made in a 110 MW steam generator in Austria with a wide range of fuels is introduced. One of the largest bituminous coal fired once-trough steam generator built by EVT is the boiler for the power station Bexbach I (750 MW). The firing system is designed as a tangential firing system with 32 jet burners. These are arranged in pairs in the corners and divided into 4 burner levels with 4 burner pairs each. One mill is allocated to each burner level. An important characteristic feature is that the four bowl mills are arranged on one side of the steam generator. The plant is constructed with upper air nozzles which are arranged above the top burner level for the reduced of nitrogen oxides. During tests at steam generator with similar design, the nO x formation could be reduced from 750 to 500 mg/m 3 s.t.p. (dry, 6% O 2 ) with an addition of upper air of 20% at 100% unit capacity and constant total flow. As a main approach for the further reduction of the primary NO x emission at bituminous coal fired steam generators with tangential firing systems, the experience gained from the firing of brown coal has also been taken into account. A fundamental aspect in this respect was the vertical air staging in the direction of the furnace height. The results of many tests in a test reactor have shown that the differences of the achievable NO x values of brown and

  16. Analysis of the planned post-mining landscape of MIBRAG's open-cast mines with regard to a possible environmental impact of alteration processes in mixed dumps

    Energy Technology Data Exchange (ETDEWEB)

    Jolas, P.; Hofmann, B. [Mitteldeutsche Braunkohlengesellschaft, Theissen (Germany)

    2010-07-01

    There has been an increasing body of knowledge with regard to hydro- and geochemical alteration processes in overburden dumps and their impact on groundwater quality in lignite mining and reclamation operations associated with post-mining landscapes in Germany. The operators of the MIBRAG mines have examined issues regarding alteration processes and how they affect the environment and which opportunities exist to actively influence the dumping process. The objectives were to counteract any possible negative impact of the alteration processes. Special emphasis was on the impact caused by oxidation of sulfur containing minerals. This paper presented an analysis of the situation at United Schleenhain Mine and how it reflects on the work to date for MIBRAG's mines. A future outlook was also presented. Specifically, the paper discussed the development of the United Schleenhain mine and the post-mining landscape. The potential for discharge of substances was also evaluated along with acidification. 1 tab., 5 figs.

  17. Ordered microporous layered lanthanide 1,3,5-benzenetriphosphonates pillared with cationic organic molecules.

    Science.gov (United States)

    Araki, Takahiro; Kondo, Atsushi; Maeda, Kazuyuki

    2015-04-13

    Novel isomorphous pillared-layer-type crystalline lanthanide 1,3,5-benzenetriphosphonates were prepared with bpy and dbo as organic pillars (LnBP-bpy and LnBP-dbo; Ln: Ce, Pr, and Nd). Ab initio crystal structure solution using synchrotron X-ray powder diffraction data revealed that the organic pillars do not exist as neutral coordinating ligands but as cationic molecules. Especially the LnBP-dbo phases have ordered interlayer space filled with water molecules between the dbo pillars, and the interlayer water is successfully removed by heating under vacuum with slightly distorted but basically retained pillared layer structures. Microporosity of the materials is confirmed by adsorption of nitrogen, carbon dioxide, and hydrogen gases. Such microporous layered metal phosphonates pillared with cationic molecules should be unprecedented and should offer new strategies to design ordered microporous materials. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Constraint effects of model coal pillar geometry on its strength

    Energy Technology Data Exchange (ETDEWEB)

    Wahab Khair, A.; Danqing Xu (West Virgina University, Morgantown, WV (United States))

    1994-06-01

    Coal and rock specimens with various diameter/height ratios (D/H) were subjected to compressive test in the laboratory. The deformation and failure characteristics of specimens were studied. The study showed that the D/H ratio of specimens significantly affects the deformation, failure characteristics, and the strength of material. The results provide a better understanding of the mechanism of D/H ratio effect on the strength of materials. The magnitude and mechanism of D/H ratio effect was compared with the effect of confining pressure, and contrasted to size effect. The application of the study to pillar design is discussed. 3 refs., 10 figs.

  19. Dry re-forming of methane to synthesis gas over lignite semicokes catalyst at high pressure

    Directory of Open Access Journals (Sweden)

    Fengbo Guo

    2016-11-01

    Full Text Available Dry re-forming of methane has been carried out in a high temperature–pressure reactor at different pressures, using Hongce lignite semicokes catalyst. The results show that CH4 and CO2 conversions are decreased as the reaction pressure increased, but both of them kept basically stable when the reaction pressure is between 0.3 and 1 MPa. The comparison shows that the effects of the temperature and the flow of reactant gas on dry re-forming of methane are consistent with between high pressure and atmospheric pressure. The ratio of CO/H2 decreased as the ratio of CH4/CO2 increased, yet the value of CO/H2 is always more than 1 at different pressures. Hongce lignite semicokes catalyst is characterized by FTIR, XRD, SEM and BET, and the analysis results reveled that the physical specific adsorption peak of CO2 at 2350 cm−1 is strengthened significantly at different pressures, the micropore area and volume of Hongce lignite semicokes reduced form 40.2 m2  g−1 and 0.019 cm3  g−1 to 34.9 m2  g−1 and 0.017 cm3  g−1, respectively. Hongce lignite semicokes catalyst exhibited better activity and stability within 0.3–1 MPa range.

  20. Elemental characterization of lignite from Afsin-Elbistan in Turkey by k(0)-NAA

    Czech Academy of Sciences Publication Activity Database

    Kubešová, Marie; Orucoglu, E.; Haciyakupoglu, S.; Erenturk, S.; Krausová, Ivana; Kučera, Jan

    2016-01-01

    Roč. 308, č. 3 (2016), s. 1055-1062 ISSN 0236-5731 R&D Projects: GA ČR(CZ) GBP108/12/G108; GA MŠk(CZ) LM2011019 Institutional support: RVO:61389005 Keywords : Lignite * Afsin * Elbistan * neutron activation analysis * k(0) standardization Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.282, year: 2016

  1. Process for treating bituminous coal, lignite, peat, and shale, and products obtained

    Energy Technology Data Exchange (ETDEWEB)

    Schabelitz, E J

    1951-06-27

    A process is described comprising leaching bituminous coal, lignite, peat, or shale by immersing said material in ethylene dichloride for a period of time sufficient to remove the ethylene dichloride-soluble constituents, separating the treated material from the ethylene dichloride solution and recovering from the solution the soluble constituents of the material dissolved in the solution. Soluble constituents include oils and waxes.

  2. Co-gasification of a lignite/waste-tyre in a moving bed

    Czech Academy of Sciences Publication Activity Database

    Straka, Pavel; Bučko, Z.

    2009-01-01

    Roč. 90, č. 10 (2009), s. 1202-1206 ISSN 0378-3820 R&D Projects: GA ČR(CZ) GA105/07/1407 Institutional research plan: CEZ:AV0Z30460519 Keywords : co-gasification * waste-tyre * lignite Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.321, year: 2009

  3. A modern thermal power station operating on high-moisture lignite

    Energy Technology Data Exchange (ETDEWEB)

    V.R. Kotler; D.V. Sosin [All-Russia Thermal Engineering Institute (VTI), Moscow (Russian Federation)

    2009-07-01

    The boilers developed by the power machinery construction company Alstom for two power-generating units, the Maritsa East-II and Maritsa East-II, operating on high-moisture lignite from the Maritsa East field in Bulgaria are described.

  4. Evaluating Pillar Industry's Transformation Capability: A Case Study of Two Chinese Steel-Based Cities.

    Science.gov (United States)

    Li, Zhidong; Marinova, Dora; Guo, Xiumei; Gao, Yuan

    2015-01-01

    Many steel-based cities in China were established between the 1950s and 1960s. After more than half a century of development and boom, these cities are starting to decline and industrial transformation is urgently needed. This paper focuses on evaluating the transformation capability of resource-based cities building an evaluation model. Using Text Mining and the Document Explorer technique as a way of extracting text features, the 200 most frequently used words are derived from 100 publications related to steel- and other resource-based cities. The Expert Evaluation Method (EEM) and Analytic Hierarchy Process (AHP) techniques are then applied to select 53 indicators, determine their weights and establish an index system for evaluating the transformation capability of the pillar industry of China's steel-based cities. Using real data and expert reviews, the improved Fuzzy Relation Matrix (FRM) method is applied to two case studies in China, namely Panzhihua and Daye, and the evaluation model is developed using Fuzzy Comprehensive Evaluation (FCE). The cities' abilities to carry out industrial transformation are evaluated with concerns expressed for the case of Daye. The findings have policy implications for the potential and required industrial transformation in the two selected cities and other resource-based towns.

  5. Mining aspects of hard to access oil sands deposits

    Energy Technology Data Exchange (ETDEWEB)

    Stephenson, G.; Wright, D.; Lukacs, Z. [Norwest Corp., Calgary, AB (Canada)

    2006-07-01

    While a variety of oil sands mining technologies have been explored since the 1960s, the oil sands industry has generally favoured truck and shovel mining as a proven, low-cost mining solution. However, surface mining economics are affected by the price of bitumen, haul distances, tailings storage and geotechnical constraints. Maintenance, labour and the cost of replacing tires and ground engaging tools also have a significant impact on the economics of surface mining. Large volumes of water are used in surface mining, and remediation of surface mined areas can take hundreds of years. Damage to machinery is common as oil sands are abrasive and adhere to equipment. This presentation examined recent technologies developed to improve the economics of surface mining. Various extraction and tailings technologies were reviewed. Issues concerning the integration of mining and extraction processes were discussed. Various monitoring tools were evaluated. A review of new underground mining options included outlines of: longwall mining; sub-level caving; tunnel boring; and room and pillar extraction techniques. A generalized regional geology was presented. It was concluded that the oil sands surfacing mining industry should concentrate on near-term research needs to improve the performance and economics of proven technologies. Screening studies should also be conducted to determine the focus for the development of underground technologies. refs., tabs., figs.

  6. Argilas pilarizadas - uma introdução An introduction to pillared clays

    Directory of Open Access Journals (Sweden)

    Fernando J. Luna

    1999-02-01

    Full Text Available The synthesis, characterization and some applications in catalysis of pillared clays are described at an introductory level. The use of x-ray diffraction, surface area measurements, thermal analysis, IR spectrophotometry and solid-state NMR in the characterization of pillared clays is briefly discussed. Pillarization followed by doping or introduction of metal clusters into clays could lead to the development of selective heterogeneous catalysts.

  7. New aeration systems for higher efficiency in mine water treatment in the Lausitz region; Einsatz neuer Belueftungssysteme zur Effizienzsteigerung bei der Grubenwasserbehandlung in der Lausitz

    Energy Technology Data Exchange (ETDEWEB)

    Janneck, E.; Glombitza, F. [G.E.O.S. Freiberg Ingenieurgesellschaft mbH, Freiberg (Germany); Schlee, K.; Arnold, I. [Vattenfall Europe Mining AG, Cottbus (Germany)

    2006-07-01

    The article presents experiences and results of the application of new aerator-systems in the mine water treatment. The processes of ferrous iron oxidation and sludge removal became more stable and efficiently by the application of the aerators. For the first time, spiral aerators were used in the Lower Lusatia lignite mining district to clean ferrous iron containing mine water. These devices lead to an enhanced iron oxidation rate under the existing conditions, where the oxygen diffusion is the rate determining step. Furthermore, the application caused increased throughput, optimal lime utilisation and better sludge thickening, which led to a higher efficiency of the mine water treatment. (orig.)

  8. Manipulating the optical properties of CdSe/ZnSSe quantum dot based monolithic pillar microcavities

    Energy Technology Data Exchange (ETDEWEB)

    Seyfried, Moritz; Kalden, Joachim; Lohmeyer, Henning; Sebald, Kathrin; Gutowski, Juergen [Semiconductor Optics, Institute of Solid state Physics, University of Bremen (Germany); Kruse, Carsten; Hommel, Detlef, E-mail: Seyfried@ifp.uni-bremen.d [Semiconductor Epitaxy, Institute of Solid state Physics, University of Bremen (Germany)

    2010-02-01

    A customization of the optical properties of pillar microcavities on the desired applications is essential for their future use as quantum-optical devices. Therefore, all-epitaxial cavities with CdSe quantum dot embedded in pillar structures with different geometries have been realized by focused-ion-beam etching. The quality factors of circularly shaped pillar microcavities have been measured and their dependence on the excitation power is discussed. As a possibility to achieve polarized light emission, asymmetrically shaped microcavities are presented. Examples of an elliptically shaped pillar as well as of photonic molecules are investigated with respect to their photoluminescence characteristics and polarization.

  9. Policy framework for utilisation. A pillar of better accessibility

    International Nuclear Information System (INIS)

    2008-01-01

    The goals and frameworks for traffic and transport policy for the Netherlands to 2020 are described in the Mobility Document. Whereas government policy previously viewed mobility as a problem or as something permissible, the assumption is now that mobility is a must. Mobility, for people as well as goods, is a prerequisite for society and the economy to function well. The Mobility Document contains ambitious goals to deal with current and anticipated traffic and transport problems: door to door, faster, cleaner and safer. Three interrelated pillars are to help achieve these goals: Building, Pricing and Utilisation. Work is being done on the Building and Pricing pillars; Utilisation is elaborated further in this policy framework. The Policy Framework for Utilisation is an elaboration of the Mobility Document for the 2008-2020 period and aims for faster, cleaner, safer travel from door to door. The purpose of this policy framework is to describe the direction of development of utilisation, in terms of content as well as process, to indicate actions that are required and to provide perspective on the expected effects. The policy framework is in line with current developments or plans, caters to new opportunities (technological and otherwise), encourages the innovative potential of the market and provides room for joint ventures between the government and the market. It will result in actions for the short term and provide direction for activities and developments for the longer term

  10. Mine drivage in hydraulic mines

    Energy Technology Data Exchange (ETDEWEB)

    Ehkber, B Ya

    1983-09-01

    From 20 to 25% of labor cost in hydraulic coal mines falls on mine drivage. Range of mine drivage is high due to the large number of shortwalls mined by hydraulic monitors. Reducing mining cost in hydraulic mines depends on lowering drivage cost by use of new drivage systems or by increasing efficiency of drivage systems used at present. The following drivage methods used in hydraulic mines are compared: heading machines with hydraulic haulage of cut rocks and coal, hydraulic monitors with hydraulic haulage, drilling and blasting with hydraulic haulage of blasted rocks. Mining and geologic conditions which influence selection of the optimum mine drivage system are analyzed. Standardized cross sections of mine roadways driven by the 3 methods are shown in schemes. Support systems used in mine roadways are compared: timber supports, roof bolts, roof bolts with steel elements, and roadways driven in rocks without a support system. Heading machines (K-56MG, GPKG, 4PU, PK-3M) and hydraulic monitors (GMDTs-3M, 12GD-2) used for mine drivage are described. Data on mine drivage in hydraulic coal mines in the Kuzbass are discussed. From 40 to 46% of roadways are driven by heading machines with hydraulic haulage and from 12 to 15% by hydraulic monitors with hydraulic haulage.

  11. Mining of sedimentary-type ore deposits

    International Nuclear Information System (INIS)

    Bruha, J.; Slovacek, T.; Berka, J.; Sadilek, P.

    1992-01-01

    A procedure is proposed for mining sedimentary-type ore deposits, particularly uranium deposits, using the stope-pillar technique. The stope having been mined out, the free room is filled with hydro-setting gob from the surface. A precondition for the application of this technique is horizontal ore mineralization in sediments where the total thickness of the mineralized ore layer is at least 3 to 5 m. Mining losses do not exceed 5%. For thicknesses greater than 5 m, the roof is reinforced and the walls are secured with netting. The assets of the technique include higher labor productivity of the driving, lower material demands in reinforcing and filling, lower power consumption, and reduced use of explosives. (Z.S.). 3 figs

  12. Bagged stone dust barrier evaluations in a bord and pillar mine

    CSIR Research Space (South Africa)

    Du Plessis, JJL

    2000-05-01

    Full Text Available at LLEM . . 20 5 Program of work . . . . . . 21 5.1 Description of methane tests (Phase I) . . . 22 5.2 Description of coal dust explosion tests (Phase II) . 29 6 5.2.1 First coal dust baseline explosion: LLEM test #389 . . 30 5.2.2 Second coal dust...: LLEM test #394 . . . . 36 5.3 Evaluation methodology . . . . . 37 5.3.1 Methane tests evaluation methods . . . . 37 5.3.2 Barrier evaluation criteria . . . . . . 40 6 Test barrier . . . . . . . 41 6.1 Proposed distributed bagged stone dust barrier...

  13. Web Mining

    Science.gov (United States)

    Fürnkranz, Johannes

    The World-Wide Web provides every internet citizen with access to an abundance of information, but it becomes increasingly difficult to identify the relevant pieces of information. Research in web mining tries to address this problem by applying techniques from data mining and machine learning to Web data and documents. This chapter provides a brief overview of web mining techniques and research areas, most notably hypertext classification, wrapper induction, recommender systems and web usage mining.

  14. Text Mining.

    Science.gov (United States)

    Trybula, Walter J.

    1999-01-01

    Reviews the state of research in text mining, focusing on newer developments. The intent is to describe the disparate investigations currently included under the term text mining and provide a cohesive structure for these efforts. A summary of research identifies key organizations responsible for pushing the development of text mining. A section…

  15. Surface mining

    Science.gov (United States)

    Robert Leopold; Bruce Rowland; Reed Stalder

    1979-01-01

    The surface mining process consists of four phases: (1) exploration; (2) development; (3) production; and (4) reclamation. A variety of surface mining methods has been developed, including strip mining, auger, area strip, open pit, dredging, and hydraulic. Sound planning and design techniques are essential to implement alternatives to meet the myriad of laws,...

  16. Uranium mining

    International Nuclear Information System (INIS)

    Lange, G.

    1975-01-01

    The winning of uranium ore is the first stage of the fuel cycle. The whole complex of questions to be considered when evaluating the profitability of an ore mine is shortly outlined, and the possible mining techniques are described. Some data on uranium mining in the western world are also given. (RB) [de

  17. Iron precipitates in the Lusatian lignite district. Part 2: Geochemistry and genesis of incrustation; Eisenausfaellungen im Lausitzer Braunkohlerevier. Teil 2: Geochemie und Genese der Inkrustierung

    Energy Technology Data Exchange (ETDEWEB)

    Uhlmann, W.; Arnold, I. [IWB - Institut fuer Wasser und Boden, Dresden (Germany)

    2003-09-01

    Part 1 of this contribution (published in issue 03/2002) dealt with the hydrochemistry of sump water from the open pit lignite mine Nochten and its variation during the course to the mine water purification plant Schwarze Pumpe. Sump water is transferred to the purification plant via an approx. 7000 m long open channel (former river course) followed by a 6700 m long closed GFK pipeline DN 1200. Operation of the pipeline started in summer 1998. Only a few months after the start of operation of the GFK pipeline a distinct decrease in efficiency was recorded. The reason of this decrease in efficiency was determined to be a 1.5 cm thick incrustation in the pipeline after one year of operation, which leads to a reduction of the pipeline's cross section. The incrustation exhibits a scaly structure with an extremely high surface roughness. This roughness is the main reason for the efficiency decrease of the pipeline. In part 2, the results of extensive geochemical investigations are shown and discussed. The incrustation was chemically and mineralogically identified to be the mineral schwertmannite. The formation of schwertmannite can be described by hydrochemical modelling and can therefore be quantified. Investigations are carried out, which examine the subject of avoidance and elimination of incrustations from a chemical point of view. (orig.)

  18. Study on the optimum design of bus window pillar join40t; Bus window pillar ketsugo buzai no saiteki sekkei ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Tomioka, N [Nihon University, Tokyo (Japan); Lim, S; Kim, M; Lee, H; Kang, S; Bae, D

    1997-10-01

    Automobile body structure is generally assembled using various spot welded box sectional members. Especially, in the case of the bus, the shape of window pillar joint is assembled m T-type. This T-type member has some problem such as high stress concentration, low fatigue strength and structural rigidity. Therefore, in this report, performed a study on the optimum design of the bus window pillar joint for such problem by FEM analysis and experiments. 1 ref., 10 figs., 2 tabs.

  19. Protecting mine roadways used for the second time in the Komsomolets Donbassa mine

    Energy Technology Data Exchange (ETDEWEB)

    Zaslavskii, I Yu; Boev, N A; Churakov, V N

    1983-12-01

    This paper evaluates methods for strata control in gate roads used in the Komsomolets Donbassa mine with 2 coal seams from 1 to 1.1 m thick at depths of 418 m and 624 m, with dip angles from 5 to 10 degrees. Long pillars are mined by a system of longwall faces with caving. The following methods for strata control in gate roads are comparatively evaluated: use of blocks made of reinforced concrete, use of timber cribbings, combined use of concrete blocks or cribbings and strips of pneumatic stowing from 8 to 12 m wide, use of thin coal support pillars (from 2 to 3 m). Investigation results are shown in 4 diagrams. Analyses show that use of blocks made of reinforced concrete or concrete blocks combined with strips of pneumatic stowing does not prevent excessive roof subsidence and support deformation. Use of coal support pillars from 2 to 3 m wide is not recommended due to considerable cost and coal losses. Use of timber cribbings combined with strips of pneumatic stowing is most expedient. Recommendations on using timber cribbings and pneumatic stowing for strata control in gate roads used by the next longwall face are made. (In Russian)

  20. Prairie of mine(s) : cultural reclamation of the Estevan/Bienfait Coalfields

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, S.

    2010-07-01

    A cultural reclamation project was launched in the Bienfait region of southern Saskatchewan where lignite mining has been ongoing since the 1800s. Evidence of 5 surface mines, 2 power stations and thousands of acres of spoil piles remain at the abandoned site. The region also comprises 140 abandoned underground mines and 4 mined-out townsites. The project introduced cultural reclamation into the role of landscape architecture, specifically in the planning and design of reclaimed mining lands. At the present time, the reclamation of post-extractive sites is limited to focusing almost exclusively on ecological factors, but failing to recognize the people and the industrial processes that actively transformed the landscape can disengage people from their past. The project concludes with a proposed master plan in addition to a few site-specific interventions that interrogate and explore the role of experiential, cultural, and historical elements in the reclamation of a site. In doing so, awareness is created about the ways in which various landscapes are manipulated every day in order for people to live in greater comfort.

  1. State and performance of on-stream ash content determination in lignite and black coal using 2-energy transmission technique

    International Nuclear Information System (INIS)

    Thuemmel, H.W.; Koerner, G.; Leonhardt, J.

    1986-01-01

    The total r.m.s. ash error of the 2-energy transmission on-stream ash gauges KRAS-2 (CIIRR, GDR) and SIROASH (Australia) are 4 weight percentage for raw lignite and 0.5 weight percentage for black coal, respectively. A detailed error analysis shows that this difference is due to the high water content and to strong variations in the ash composition of raw lignite. Both gauges show essentially the same radiometric performance. (author)

  2. Infilling Littleton Street Mine, Wallsall, with colliery spoil rock paste

    Energy Technology Data Exchange (ETDEWEB)

    Jarvis, S.T.; Braithwaite, P.A. [Ove Arup and Partners, Birmingham (United Kingdom)

    1993-12-31

    Describes the filling of an abandoned underground mine with low strength (12-20 kPa) paste made of coal mining waste. With a volume of 550,000 m{sup 3}, it was the largest mine to be filled with rock paste to date. The abandoned mine, flooded with underground water, consists of room and pillar workings at shallow depth of 35 to 60 m. Height of the underground mine cavity varies between 4 and 8 m. The process of infilling and tests and systems for monitoring infilling completeness and strength are described. Benefits of rock paste over other forms of infilling are discussed. Land reclamation work at the source sites is also described. Mineral waste source sites and specifications of the materials are given. After work completion, about 18 ha of derelict urban land were released for redevelopment. 6 refs.

  3. The Sloan-C Pillars: Towards a Balanced Approach to Measuring Organizational Learning

    Science.gov (United States)

    Yeo, Kee Meng; Mayadas, A. Frank

    2010-01-01

    The Sloan Pillars have set the standard for university-wide online learning program assessment for more than a dozen years. In this paper, the authors propose the extension of the Pillars to corporate e-learning, offering an alternative to traditional enterprise learning assessments. Claiming that conventional methods stress individual courses or…

  4. Workshops around the pillar system design computer program produced in SIMRAC project GAP334

    CSIR Research Space (South Africa)

    York, G

    2000-03-01

    Full Text Available with the actual Pillar System Design program. Four workshops were held, three in the Bushveld Complex, and one at the Conference Centre at CSIR Miningtek. The delegates comprised most of the industry rock mechanics practitioners who deal with pillar system design...

  5. Fates and roles of alkali and alkaline earth metal species during the pyrolysis and gasification of a Victorian lignite

    Energy Technology Data Exchange (ETDEWEB)

    Mody, D.; Wu, H.; Li, C. [Monash University, Vic. (Australia). CRC for Clean Power from Lignite, Dept. of Chemical Engineering

    2000-07-01

    The transformation of alkali and alkaline earth metal (AAEM) species in a Victorian lignite during the pyrolysis and subsequent gasification in CO{sub 2} was studied in a novel quartz fluidised-bed reactor. Lignite samples prepared by physically adding NaCl and ion-exchanging Na{sup +} and Ca{sup ++} into the lignite were used to investigate the effects of chemical forms and valency of the AAEM species in the substrate lignite on their transformation during pyrolysis and gasification. Carboxyl-bound Na was found to be less volatile than Na present as NaCl, but more volatile than carboxyl-bound Ca during pyrolysis at temperatures between 400 and 900{sup o}C. However, the carboxyl-bound Na was volatilised to a much greater extent than the carboxyl-bound Ca in the same lignite during pyrolysis. It was seen that the loading of NaCl into the lignite did not significantly affect the char reactivity in the fluidised-bed reactor at 900{sup o}C.

  6. A comparative study of nitrogen conversion during pyrolysis of coconut fiber, its corresponding biochar and their blends with lignite.

    Science.gov (United States)

    Liu, Zhengang; Balasubramanian, Rajasekhar

    2014-01-01

    In the present study, the conversion of fuel-N to HCN and NH3 was investigated during rapid pyrolysis of raw biomass (coconut fiber), its corresponding biochar and their blends with lignite within a temperature range of 600-900°C. The results showed that the raw biomass and the biochar showed totally different nitrogen partitioning between NH3 and HCN. HCN was the dominant nitrogen pollutant from pyrolysis of raw biomass, while for the biochar pyrolysis the yield of NH3 was slightly higher than that of HCN. Synergistic interactions occurred within both raw biomass/lignite and biochar/lignite blends, especially for the biochar/lignite blend, and resulted in reduced yields of HCN and NH3, decreased the total nitrogen percentage retained in the char and promoted harmless N2 formation. These findings suggest that biochar/lignite co-firing for energy production may have the enhanced benefit of reduced emissions of nitrogen pollutants than raw biomass/lignite. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Four pillars of radio astronomy Mills, Christiansen, Wild, Bracewell

    CERN Document Server

    Frater, R H; Wendt, H W

    2017-01-01

    This is the story of Bernie Mills, Chris Christiansen, Paul Wild and Ron Bracewell, members of a team of radio astronomers that would lead Australia, and the world, into this new field of research. Each of the four is remembered for his remarkable work: Mills for the development the cross type instrument that now bears his name; Christiansen for the application of rotational synthesis techniques; Wild for the masterful joining of observations and theory to elicit the nature of the solar atmosphere; Bracewell for his contribution to imaging theory. As well, these Four Pillars are remembered for creating a remarkable environment for scientific discovery and for influencing the careers of future generations. Their pursuit of basic science helped pave the way for technological developments in areas ranging from Wi-Fi to sonar to medical imaging to air navigation, and for underpinning the foundations of modern cosmology and astrophysics.

  8. Environmental management as a pillar for sustainable development.

    Science.gov (United States)

    Mikulčić, Hrvoje; Duić, Neven; Dewil, Raf

    2017-12-01

    There is a growing concern about how to minimize the impact of human activities on the environment. Already nowadays, in some places adaptation efforts are needed in order to avoid the irreversibility of negative human activities. Due to climate changes, and corresponding environmental and social changes, there is a great need for a more sustainable development of mankind. Over the years, research studies that analyzed the sustainable development of different communities with a multi-disciplinary approach, stressed the necessity of preserving the environment for next generations. Therefore, responsible and conscientious management of the environment is a pillar of the sustainable development concept. This review introduction article provides an overview of the recent top scientific publications related to sustainable development that mostly originated from previous SDEWES conferences. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Three Pillars for the Neural Control of Appetite.

    Science.gov (United States)

    Sternson, Scott M; Eiselt, Anne-Kathrin

    2017-02-10

    The neural control of appetite is important for understanding motivated behavior as well as the present rising prevalence of obesity. Over the past several years, new tools for cell type-specific neuron activity monitoring and perturbation have enabled increasingly detailed analyses of the mechanisms underlying appetite-control systems. Three major neural circuits strongly and acutely influence appetite but with notably different characteristics. Although these circuits interact, they have distinct properties and thus appear to contribute to separate but interlinked processes influencing appetite, thereby forming three pillars of appetite control. Here, we summarize some of the key characteristics of appetite circuits that are emerging from recent work and synthesize the findings into a provisional framework that can guide future studies.

  10. Integrated pillar scatterers for speeding up classification of cell holograms.

    Science.gov (United States)

    Lugnan, Alessio; Dambre, Joni; Bienstman, Peter

    2017-11-27

    The computational power required to classify cell holograms is a major limit to the throughput of label-free cell sorting based on digital holographic microscopy. In this work, a simple integrated photonic stage comprising a collection of silica pillar scatterers is proposed as an effective nonlinear mixing interface between the light scattered by a cell and an image sensor. The light processing provided by the photonic stage allows for the use of a simple linear classifier implemented in the electric domain and applied on a limited number of pixels. A proof-of-concept of the presented machine learning technique, which is based on the extreme learning machine (ELM) paradigm, is provided by the classification results on samples generated by 2D FDTD simulations of cells in a microfluidic channel.

  11. Evaporation-driven clustering of microscale pillars and lamellae

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae-Hong; Kim, Jungchul; Kim, Ho-Young, E-mail: hyk@snu.ac.kr [Department of Mechanical and Aerospace Engineering, Seoul National University, Seoul 08826 (Korea, Republic of)

    2016-02-15

    As a liquid film covering an array of micro- or nanoscale pillars or lamellae evaporates, its meniscus pulls the elastic patterns together because of capillary effects, leading to clustering of the slender microstructures. While this elastocapillary coalescence may imply various useful applications, it is detrimental to a semiconductor manufacturing process called the spin drying, where a liquid film rinses patterned wafers until drying. To understand the transient mechanism underlying such self-organization during and after liquid evaporation, we visualize the clustering dynamics of polymer micropatterns. Our visualization experiments reveal that the patterns clumped during liquid evaporation can be re-separated when completely dried in some cases. This restoration behavior is explained by considering adhesion energy of the patterns as well as capillary forces, which leads to a regime map to predict whether permanent stiction would occur. This work does not only extend our understanding of micropattern stiction, but also suggests a novel path to control and prevent pattern clustering.

  12. Cu Pillar Low Temperature Bonding and Interconnection Technology of for 3D RF Microsystem

    Science.gov (United States)

    Shi, G. X.; Qian, K. Q.; Huang, M.; Yu, Y. W.; Zhu, J.

    2018-03-01

    In this paper 3D interconnects technologies used Cu pillars are discussed with respect to RF microsystem. While 2.5D Si interposer and 3D packaging seem to rely to cu pillars for the coming years, RF microsystem used the heterogeneous chip such as GaAs integration with Si interposers should be at low temperature. The pillars were constituted by Cu (2 micron) -Ni (2 micron) -Cu (3 micron) -Sn (1 micron) multilayer metal and total height is 8 micron on the front-side of the wafer by using electroplating. The wafer backside Cu pillar is obtained by temporary bonding, thinning and silicon surface etching. The RF interposers are stacked by Cu-Sn eutectic bonding at 260 °C. Analyzed the reliability of different pillar bonding structure.

  13. Contract Mining versus Owner Mining

    African Journals Online (AJOL)

    Owner

    mining companies can concentrate on their core businesses while using specialists for ... 2 Definition of Contract and Owner. Mining ... equipment maintenance, scheduling and budgeting ..... No. Region. Amount Spent on. Contract Mining. ($ billion). Percent of. Total. 1 ... cost and productivity data based on a large range.

  14. New developments in uranium mining in India

    International Nuclear Information System (INIS)

    Puri, R.C.

    1993-01-01

    Uranium mining is so far restricted to underground mines only. Uranium mining is similar to other non-coal (metalliferous) mining. Mode of entries has been adits, inclines and vertical shafts. Decline have been constructed at Narwapahar and Turamdih. Access decline (7 deg) at Narwapahar has been driven to about 900 m length and reached depth of about 100 m. Stoping methods are mainly with filling, open stopes supported with adequate pillars with or without post filling to prevent surface subsidence are also being adopted. Appreciable degree of mechanization has been adopted in Jaduguda mines however, Narwapahar mine has been made highly mechanized. Face mechanization in the present operations is by way of air leg mounted jack hammers and stope wagons for drilling and small capacity (upto 1 cu. yd) rail mounted/trackless loaders for loading. Alimak raise climber has been used for raising work. For horizontal transport in mines, Hunselet diesel locomotives (4 tonne size) with Granby car, 3.5 tonne capacity, are being used, vertical transport is by means of drum winders and tower mounted friction winders. At Narwapahar mine twin boom drill jumobs, LHDs-1.78 m 3 and 2.8 m 3 capacity, PLDTs-15 tonner and 23 tonner capacity and relevant service equipment like passenger carriers, supply trucks, service cum lube truck, motor grader, etc. are being used. These rubber tyrred trackless equipment enter the mine directly from the surface through the service/access decline entry. These new developments in mining are detailed hereinafter. (author). 11 figs., 4 photos

  15. Solubilization of low-rank coal by Trichoderma atroviride: Evidence for the involvement of hydrolytic and oxidative enzymes by using C-14-labelled lignite

    Energy Technology Data Exchange (ETDEWEB)

    Holker, U.; Schmiers, H.; Grosse, S.; Winkelhofer, M.; Polsakiewicz, M.; Ludwig, S.; Dohse, J.; Hofer, M. [University of Bonn, Bonn (Germany). Inst. of Botany

    2002-04-01

    The deuteromycete Trichoderma atroviride is able to solubilize lignite in dependence on a given carbon source for growth. When cultivated on media containing glutamate, this mold excreted a set of different enzymes with hydrolytic activity. Addition of lignite to the growth media induced the synthesis of extracellular lignite-specific esterase activity but no evidence has been provided for its direct involvement in the process of lignite solubilization. Hence, the basic capability of T. atroviride enzymes to degrade a variety of ester and ether bonds at the surface or within the bulky lignite structure was tested using coal following its direct labelling with C-14-alkyl iodide. The participation of hydrolytic and oxidative enzymes in lignite degradation was assessed by measuring the release of C-14 radioactivity from selectively alkylated carboxylic and phenolic OH groups. T. atroviride cleaved both carboxylic esters using esterases and the phenolic ether bonds by using oxidative enzymes, most likely laccases.

  16. Investigation of subsidence event over multiple seam mining area

    International Nuclear Information System (INIS)

    Kohli, K.K.

    1999-01-01

    An investigation was performed to determine the sequence of events which caused the 1987 surface subsidence and related damage to several homes in Walker County, Alabama, USA. Surface affects compared to mine maps indicated the subsidence to be mine related. However, two coal seams had been worked under this area. The upper seam, the American seam, ranged from 250 to 280 feet beneath the surface in the area in question. It was mined-out before 1955 by room-and-pillar method leaving in place narrow-long pillars to support the overburden strata, and abandoned in 1955. The lower seam, the Mary Lee seam, ranged from 650 to 700 feet beneath the surface. The Mary Lee seam had been abandoned in 1966 and subsequently became flooded. The dewatering of the Mary Lee seam workings in 1985 caused the submerged pillars to be exposed to the atmosphere. Due to multiple seam mining and the fact that workings had been inundated then dewatered, a subsurface investigation ensued to determine the sequence and ultimate cause of surface subsidence. Core sample tests with fracture analysis in conjunction with down-the-hole TV camera inspections provided necessary information to determine that the subsidence started in the lower seam and progressed through the upper coal seam to the surface. Evidence from the investigation program established that dewatering of the lower seam workings caused the marginally stable support pillars and the roof to collapse. This failure triggered additional subsidence in the upper seam which broadened the area of influence at the surface

  17. γ-ray activity in bituminous, subbituminous and lignite coals

    International Nuclear Information System (INIS)

    Barber, D.E.; Giorgio, H.R.

    1977-01-01

    Specimens of three different types of coal from four different geographical locations (Montana, North Dakota, Illinois and Pennsylvania) were examined by γ-ray spectrometry. Some samples were ashed in a muffle furnace. Other samples included pulverized coal, slag and fly ash from an electric power generating station. Activity from the 232 Th and 238 U series was present in all samples. Activity varied widely depending upon the source of the coal. The results indicate a need for additional examination of activity in coal to: (1) establish more precisely the relative environmental impact of coal-fired power stations compared with nuclear ones, (2) indicate the degree of sophistication required in environmental surveillance programs involving areas where both nuclear and coal-fired power stations are operational, and (3) determine the occupational exposure risks in mining operations. (author)

  18. Enrichment of Macedonian lignite through briquetting. Demonstration pilot-plant

    International Nuclear Information System (INIS)

    Dimitrov, Konstantin; Kachurkov, Gjorgi; Popovski, Kiril; Armenski, Slave

    1998-01-01

    In 1997 for the first time the scientific institutes from Republic of Macedonia got the opportunity to take part in competition to realize the scientific-research activity, financed by European Union. In the area of energy it could be applied for programs TERMI and COPERNICUS. A research project is applied for the program INCO COPERNICUS 97, with participation of the following research institutes: Koppern Aufbereitungstechnik GMbH and Co.KG - Germany; ENTEGRO - Greek Company for Energy Technology - Greece; Mining Institute Skopje - Macedonia; Faculty of Mechanical Engineering, Skopje - Macedonia; Faculty of Technical Sciences, Bitola - Macedonia; Central Institute for work protection, Skopje - Macedonia; Faculty for Industrial Chemistry and Metallurgy - Bulgaria. This paper presents the aim of the research, expected results, methodology and distribution of work among the research institutes

  19. Production of fuels out of lignite and lignocelluloses; Herstellung von Brennstoffen aus Braunkohle und Lignozellulose

    Energy Technology Data Exchange (ETDEWEB)

    Naundorf, W.; Schroeder, H.W.; Trommer, D. [TU Bergakademie Freiberg (Germany)

    2001-12-01

    The acceptance towards solid fuels will increase again if its ease of use is improved, the production costs remain low for extended periods of time, and high thermal efficiencies as well as low pollutant emissions are achieved. These demands can only be met by optimal fuel processing and the use of modern fuel engineering which applies, if possible, continuous and controlled fuel and air feed technology. Two fuels are introduced which are produced out of lignite and lignocelluloses by compaction or by balling granulation. Considering the improvement of combustion properties, remarkable synergy effects occur due to this raw material combination. Lignocelluloses act as an ignition auxillary. Lignite functions as a binding agent, increases the fuels' fire resistance, and guarantees a long, sustained combustion with an excellent combustion rate. (orig.)

  20. Volatiles and char combustion rates of demineralised lignite and wood blends

    International Nuclear Information System (INIS)

    Yilgin, Melek; Pehlivan, Dursun

    2009-01-01

    Today, much interest is given to the utilisation of materials of plant origin as substitutions of fossil fuels in meeting energy needs to reduce the level of atmospheric pollutant emissions and global warming threat, and emphasis has been placed on the co-combustion of coal and biomass. In this study, volatiles and char combustion behaviour of the fuel pellets composed from demineralised lignite and poplar wood sawdust, were investigated in a cylindrical wire mesh basket placed in a preheated tube furnace. The results have shown that ignition times of the pellets decreased with the burning temperature and shortened further due to demineralisation of lignite. Volatiles combustion rates of the samples did not correlate well with combustion times. However, they can be correlated with their respective proximate volatile matter contents. Char burnout times decreased with increasing combustion rates and correlated well with the respective proximate fixed carbon contents of the samples. Deviations were more considerable in the case of rate data. (author)

  1. Paleoenvironmental implications from biomarker and stable isotope investigations on the Pliocene Velenje lignite seam (Slovenia)

    Energy Technology Data Exchange (ETDEWEB)

    Bechtel, A.; Sachsenhofer, R.F.; Markic, M.; Gratzer, R.; Lucke, A.; Puttmann, W. [Montan University of Leoben, Leoben (Austria)

    2003-07-01

    A Pliocene lignite seam up to 160 m thick occurs in the Velenje basin (Slovenia). The seam originated in a topogenous mire and evolved within a non-marine, transgressive setting. Differences in soluble organic matter yield and hydrocarbon content of borehole samples from the lignite are related to differences in the composition of free lipids of microbial origin and/or hydrocarbons derived from the biogeochemical degradation of plant tissue. Variations of the redox conditions within the mire are reflected by pristane/phytane ratios. The abundance of terpenoid biomarkers indicates the predominance of gymnosperms over angiosperms, which is consistent with palynomorphic spectra dominated by pollen of the Sequoia-Taxodium-Metasequoia plant community rather than by angiosperms. Evidence is also provided that the content of land plant derived biomarkers and the preservation of plant tissue is controlled by the input of resin-rich, decay-resistant conifers.

  2. Physico-chemistry of adsorption of copper, nickel and cobalt on lignite from ammoniacal solutions

    International Nuclear Information System (INIS)

    Khattak, M.I.

    2004-01-01

    The present paper deals with a process developed for lignite adsorption that can be used to prevent the hard scale formation during distillation of NH/sub 3/ and CO/sub 2/, recover Cu, Ni and Cr from dilute solutions, Cu and NH/sub 3/ from waste effluent containing SO/sub 4/ radicals, separate Cu (NH/sub 3/)/sub 4//sup +2/ and AsO/sub 4//sup -3/ from ammonial solutions and recover Cu, Ni and Co from ore pulps. In additions to the study of the adsorptions of M, NH/sub 3/ and CO/sub 2/ on lignite with caustic soda) was also investigated. Changes of the functional groups of humic acid its salt, before and after the adsorption, were examined by infrared adsorption analysis. (author)

  3. Research on the thermal decomposition of Mongolian Baganuur lignite and Naryn sukhait bituminous coal

    Directory of Open Access Journals (Sweden)

    A. Ariunaa

    2016-03-01

    Full Text Available The technical characteristics, elemental composition of the organic and mineral matters, ash melting behaviors and carbonization and gasification reactivities of coals from Baganuur and Naryn sukhait deposits were investigated. The results of proximate and ultimate analysis confirmed that the coal from Baganuur deposit can be graded as a low rank lignite B2 mark coal and Naryn sukhait coal is a bituminous G mark one. The carbonization and gasification experiments were performed using TGA apparatus and fixed bed quartz reactor. The data obtained with two experimental reactors showed that Baganuur lignite had lower thermal stability and much higher CO2 gasification reactivity at 950°C as compared to those for Naryn sukhait bituminous coal.Mongolian Journal of Chemistry 16 (42, 2015, 22-29

  4. Effect of mineral oxides on slag formation tendency of Mae Moh lignites

    Directory of Open Access Journals (Sweden)

    Anuwat Luxsanayotin

    2010-08-01

    Full Text Available Slagging is one of major ash deposition problems experienced in the boilers of coal–fired power plants especially theplants that use lignite, like Mae Moh lignites. The occurrence of slag is a complex phenomenon depending on several factorssuch as ash properties, furnace operating conditions, and coal properties. The main objective of this work is to study theeffect of mineral components in Mae Moh lignite on ash fusion temperatures (AFTs, which is commonly used as a keyindicator for slag formation tendency under pulverized combustion conditions. Two Mae Moh lignites from the coal seamsplanned to be used in the future were selected for the study to represent low CaO and high CaO lignite. The two lignites,namely K1 and K3, have 3.6 and 40.4 wt% CaO in ash, respectively. The AFT characterization shows that their initial deformationtemperatures (ITs were almost identical and considered as low for the typical flue gas temperature in the radiationsection of Mae Moh boilers, i.e. 1050-1100°C. These observed similar ITs were rather unexpected, especially for K1 consideringits sufficiently low base to acid (B/A ratios. The X-ray diffraction analyses evidently show the presence of illite, pyriteand anhydrite in K1, which explains the observed lower IT of the sample. Anhydrite, which is known to lower the ITs, is alsothe most abundant mineral in K3. Washing the lignite samples with HCl can significantly reduce CaO, MgO, and SO3 contentin the ash but not Fe2O3 as it is present in the form of pyrite. The addition of Al2O3, SiO2 and Fe2O3 can help increase AFTs ofthe studied samples. The Al2O3 addition gives the strongest effect on increasing AFTs, especially for the sample with lowAl2O3 content. When the CaO is added to the low CaO samples, the fluxing effect will initially occur. However, when the CaOcontent is higher than a critical value (i.e. CaO > 38%, the effect of its high melting point will dominate hence the AFTsincreased. Ternary phase diagrams

  5. Combustion of producer gas from gasification of south Sumatera lignite coal using CFD simulation

    Directory of Open Access Journals (Sweden)

    Vidian Fajri

    2017-01-01

    Full Text Available The production of gasses from lignite coal gasification is one of alternative fuel for the boiler or gas turbine. The prediction of temperature distribution inside the burner is important for the application and optimization of the producer gas. This research aims to provide the information about the influence of excess air on the temperature distribution and combustion product in the non-premixed burner. The process was carried out using producer gas from lignite coal gasification of BA 59 was produced by the updraft gasifier which is located on Energy Conversion Laboratory Mechanical Engineering Department Universitas Sriwijaya. The excess air used in the combustion process were respectively 10%, 30% and 50%. CFD Simulations was performed in this work using two-dimensional model of the burner. The result of the simulation showed an increase of excess air, a reduction in the gas burner temperature and the composition of gas (carbon dioxide, nitric oxide and water vapor.

  6. Effect of various experimental parameters on the swelling and supercritical extraction properties of lignite

    Energy Technology Data Exchange (ETDEWEB)

    Hacimehmetoglu, S.; Sinag, A.; Tekes, A.T.; Misirlioglu, Z.; Canel, M. [Ankara University, Ankara (Turkey). Faculty of Science

    2007-07-01

    The original lignite sample, the samples swollen in dimethylsulfoxide (DMSO), dimethylformamide (DMF), pyridine, tetrahydrofuran (THF), acetone, ethylenediamine (EDA), N-methyl-2-pyrrolidone (NMP), tetrabutylammonium hydroxide (TBAH), the samples impregnated by ZnCl{sub 2} as catalyst and the samples both swollen in the solvents and impregnated by ZnCl{sub 2} were subjected to the supercritical toluene extraction and the effects of temperature, pressure, pre-swelling procedure, hydrogen donor solvent (tetralin), and catalyst on the extract yields were investigated.

  7. Catalytic effect of lignite ash on steam gasification of oil sand coke

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, E.; Palmer, A.

    1986-06-16

    Steam gasification of Suncor and Syncrude cokes was carried out in the presence of ash obtained after burning Onakawana lignite. Catalytic effects of the ash were evident at 930 C whereas at 830 C little effect was observed. These observations were attributed to the combined actions of Ca- and Fe-containing species in the ash, in which the former neutralized the sulfur in the cokes to prevent poisoning of Fe oxides. 5 tabs., 5 figs., 15 refs.

  8. Catalytic effect of mineral matter of high ash Onakawana lignite on steam gasification

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, E.

    1986-04-01

    Reactivities of untreated and acid washed Onakawana lignite during steam gasification were compared in a thermobalance reactor. The acid treatment resulted in removal of Ca, Mg, Ba and Sr from mineral matter. This was accompanied by a marked decrease in the rates of H/sub 2/, CO and CO/sub 2/ formation. The decrease of gasification rate was attributed to the decrease in concentration of gasification sites during the acid treatment.

  9. Experiments and stochastic simulations of lignite coal during pyrolysis and gasification

    International Nuclear Information System (INIS)

    Ahmed, I.I.; Gupta, A.K.

    2013-01-01

    Highlights: ► Lignite pyrolysis and gasification has been conducted in a semi batch reactor. ► The objective is to understand mechanism of syngas evolution during pyrolysis. ► Stochastic simulations of lignite pyrolysis were conducted using Gillespie algorithm. ► First order, single step mechanism failed to fit cumulative yield of hydrogen. ► Evolution of hydrogen via pyrolysis of gaseous hydrocarbon following bridges scission. -- Abstract: Lignite pyrolysis and gasification has been conducted in a semi batch reactor at reactor temperatures of 800–950 °C in 50 °C intervals. CO 2 has been used as the gasifying agent for gasification experiments. The objective of this investigation is to understand the mechanism of syngas evolution during pyrolysis and to unravel the effect of CO 2 on pyrolysis mechanism. Stochastic simulations of lignite pyrolysis have been conducted using Gillespie algorithm. Two reaction mechanisms have been used in the simulations; first order, single step mechanism and the FLASHCHAIN mechanism. The first order single step mechanism was successful in fitting cumulative yield of CO 2 , CO, CH 4 and other hydrocarbons (C n H m ). The first order, single step failed to fit the cumulative yield of hydrogen, which suggests a more complex mechanism for hydrogen evolution. Evolution of CO 2 , CO, CH 4 , C n H m and H 2 flow rates has been monitored. The only effect of CO 2 on pyrolysis mechanism is promotion of reverse water gas shift reaction for the experiments described here. Methane evolution extended for slightly longer time than other hydrocarbons and hydrogen evolution extended for a slightly longer time than methane. This indicated the evolution of hydrogen via further pyrolysis of aliphatic hydrocarbon. It is also suggested that this step occurs in series after aliphatic hydrocarbons evolution by bridges scission.

  10. Spring Barley Yield Parameters after Lignite, Sodium Humate and Nitrogen Utilization

    Directory of Open Access Journals (Sweden)

    Kováčik Peter

    2016-10-01

    Full Text Available The existence of a small number of publications dealing with the impact of solid sodium humate and lignite on the quantity and quality of grown crops was the reason for establishing the field experiment. The objective of this experiment was to detect the impact of solid lignite and solid sodium humate on the quantity and quality of spring barley yield. These substances were applied into the soil either independently or along with nitrogen fertiliser. The next objective was to determine the impact of foliar application of sodium humate water solution applied either independently or along with nitrogen fertiliser on the quality and quantity of spring barley yield. The achieved results showed that the autumn application of solid lignite and the presowing application of solid sodium humate into the soil tended to decrease the yield of both grain and straw of spring barley, crude protein content in grain, proportion of the first-class grains and volume weight of grain, whereas the impact of humate was more negative. Lignite and sodium humate in the solid form should be used along with nitrogen fertiliser. The application of sodium humate in liquid form during the growth season of barley tended to increase the yield of both grain and straw. The joint application of nitrogen and liquid sodium humate during the growth season of barley increased the grain yield of barley significantly. A lower dose of nitrogen, applied during the growth season of barley (growth season BBCH 23, increased the grain yield of barley considerably more than a higher N dose, applied into the soil before barley sowing.

  11. Synergetic use of lignite fly ash and metallurgical converter slag in geopolymer concrete

    Directory of Open Access Journals (Sweden)

    Gábor Mucsi

    2014-08-01

    Full Text Available The application and utilization of the industrial wastes and by-products in the construction industry is a key issue from an environmental and economic point of view. The increased use of lignite has substantially increased the available quantities of lignite fired power plant fly ash, which can be mainly classified as class C fly ash. The utilization of such raw material however has some difficulties. In the present paper lignite fired power station fly ash and metallurgical converter slag were used for the production of geopolymer concrete. The fly ash was used as a geopolymer based binder material, and a converter slag as aggregate, thus created a geopolymer concrete which contains mainly industrial wastes. As preliminary test experimental series were carried out using andesite as aggregate. The optimal aggregate/binder ratio was determined. The effect of the amount of alkaline activator solution in the binder, the aggregate type on the geopolymer concretes’ compressive strength and density was investigated. Furthermore, the physical properties - freeze-thaw resistance and particle size distribution - of the applied aggregates were measured as well. As a result of the experiments it was found that physical properties of the andesite and converter slag aggregate was close. Therefore andesite can be replaced by converter slag in the concrete mixture. Additionally, geopolymer concrete with nearly 20 MPa compressive strength was produced from class C fly ash and converter slag.

  12. Synthetic fuel production using Texas lignite and a very high temperature reactor for process heat

    International Nuclear Information System (INIS)

    Ross, M.A.; Klein, D.E.

    1982-01-01

    Two approaches for synthetic fuel production from coal are studied using Texas lignite as the feedstock. First, the gasification and liquefaction of coal are accomplished using Lurgi gasifiers and Fischer-Tropsch synthesis. A 50 000 barrel/day facility, consuming 13.7 million tonne/yr (15.1 million ton/yr) of lignite, is considered. Second, a nuclear-assisted coal conversion approach is studied using a very high temperature gas-cooled reactor with a modified Lurgi gasifier and Fischer-Tropsch synthesis. The nuclear-assisted approach resulted in a 35% reduction in coal consumption. In addition, process steam consumption was reduced by one-half and the oxygen plants were eliminated in the nuclear assisted process. Both approaches resulted in a synthetic oil price higher than the March 1980 imported price of $29.65 per barrel: $36.15 for the lignite-only process and $35.16 for the nuclear-assisted process. No tax advantage was assumed for either process and the utility financing method was used for both economic calculations

  13. NEW DATA ON THE LOWER PLEISTOCENE (GELASIAN LIGNITE BEDS OF CASTEL SAN PIETRO (RIETI, CENTRAL ITALY

    Directory of Open Access Journals (Sweden)

    LUCA PANDOLFI

    2017-04-01

    Full Text Available A multiproxy study of the lignite-bearing lacustrine sequence cropping out at Castel San Pietro (CSP (Rieti, central Italy provides new insights on the paleoenvironmental evolution of an extensional basin, located on the Tyrrhenian side of the Apennine range. The CSP fossiliferous levels reflect deposition in a stable lacustrine environment. Mammal remains collected from this locality during the past centuries include Stephanorhinus etruscus, Anancus arvernensis and the beaver Castor fiber. The co-existence of the Etruscan rhinoceros and the mastodont suggests a middle Villafranchian age (Montopoli or Coste San Giacomo Faunal Unit for the lignite beds of CSP. New paleoflora findings are in agreement with an attribution to the Piacenzian or Gelasian age for these deposits whilst the presence of the ostracod Qinghaicypris cf. Q. riojensis suggests a time interval from Zanclean to Gelasian (between ~4.5 and ~1.8 Ma. Accordingly, the lignite beds of CSP most likely were deposited during the Gelasian (from ca. 2.5 to 1.8 Ma; from Montopoli to Coste San Giacomo FUs or possibly to Olivola FU in forested area and warm and humid conditions.

  14. Using cement, lignite fly ash and baghouse filter waste for solidification of chromium electroplating treatment sludge

    Directory of Open Access Journals (Sweden)

    Wantawin, C.

    2004-02-01

    Full Text Available The objective of the study is to use baghouse filter waste as a binder mixed with cement and lignite fly ash to solidify sludge from chromium electroplating wastewater treatment. To save cost of solidification, reducing cement in binder and increasing sludge in the cube were focused on. Minimum percent cement in binder of 20 for solidification of chromium sludge was found when controlling lignite fly ash to baghouse filter waste at the ratio of 30:70, sludge to binder ratio of 0.5, water to mixer ratio of 0.3 and curing time of 7 days. Increase of sludge to binder ratio from 0.5 to 0.75 and 1 resulted in increase in the minimum percent cement in binder up to 30 percent in both ratios. With the minimum percent cement in binder, the calculated cement to sludge ratios for samples with sludge to binder ratios of 0.5, 0.75 and 1 were 0.4, 0.4 and 0.3 respectively. Leaching chromium and compressive strength of the samples with these ratios could achieve the solidified waste standard by the Ministry of Industry. For solidification of chromium sludge at sludge to binder ratio of 1, the lowest cost binder ratio of cement to lignite fly ash and baghouse filter waste in this study was 30:21:49. The cost of binder in this ratio was 718 baht per ton dry sludge.

  15. Combustion behavior of different kinds of torrefied biomass and their blends with lignite.

    Science.gov (United States)

    Toptas, Asli; Yildirim, Yeliz; Duman, Gozde; Yanik, Jale

    2015-02-01

    In this study, the combustion behavior of different kinds of torrefied biomass (lignocellulosic and animal wastes) and their blends with lignite was investigated via non-isothermal thermogravimetric method under air atmosphere. For comparison, combustion characteristics of raw biomasses were also determined. Torrefaction process improved the reactivity of char combustion step of biomasses. Characteristic combustion parameters for blends showed non-additivity behavior. It was found that the mixture of torrefied biomasses and lignite at a ratio of 1:1 had a lower ignition and burnout temperature than the coal-only sample. Although no interactions were observed between the lignite and torrefied biomass at initial step of combustion, a certain degree of interaction between the components occurred at char combustion step. Kinetic parameters of combustion were calculated by using the Coats Redfern model. Overall, this study showed that poultry litters can be used as a substitute fuel in coal/biomass co-firing systems by blending with lignocellulosic biomass. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Prediction of the acid generating potential of coal mining spoils

    International Nuclear Information System (INIS)

    Monterroso, C.; Macias, F.

    1998-01-01

    The sulfide oxidation impact on mined land reclamation makes it necessary for mine spoils to be classified according to their acidifying potential. In this paper predictions were made of the acid generating potential of sulfide-containing spoils from the Puentes lignite mine (Galicia, NW Spain), and the limits of sulfur contents allowable for their storage in aerobic conditions, were established. Using samples of fresh spoils, analyses were made of the content and speciation of sulfur, pH was measured after oxidation of the sample with H 2 O 2 (pH of oxidation = pH OX ), and titration of the oxidation extract with 0.1N NaOH to pH = 7 was carried out (Net Acid Production = NAP). The total sulfur content (S T ) varied between 3%, with pyritic-S being the most common form (> 80%). pH OX varied between 1.6 and 6.4 and NAP between 1.2 and 85.0 Kg-CaCO 3 t -1 . A high correlation was found between the NAP and the S T (r-0.98, p T > 0.15% cause high risks of mine-soil acidification, and create the need for large doses of CaCO 3 to be used on final surface of the mine dump. Use of fly ash, produced from the combustion of lignite, as an alternative to commercial lime is more effective in the control of acidity generated by spoils with high S T . 20 refs., 5 figs., 1 tab

  17. Analysis of lithofacies cyclicity in the Miocene Coal Complex of the Bełchatów lignite deposit, south-central Poland

    Directory of Open Access Journals (Sweden)

    Mastej Wojciech

    2015-12-01

    Full Text Available Markov chain analysis was applied to studies of cyclic sedimentation in the Coal Complex of the Bełchatów mining field (part of the Bełchatów lignite deposit. The majority of ambiguous results of statistical testing that were caused by weak, statistically undetectable advantage of either cyclicity over environmental barriers or vice versa, could be explained if only the above-mentioned advantages appeared in the neighbourhood. Therefore, in order to enhance the credibility of statistical tests, a new approach is proposed here in that matrices of observed transition numbers from different boreholes should be added to increase statistical reliability if they originated in a homogeneous area. A second new approach, which consists of revealing statistically undetectable cyclicity of lithofacies alternations, is proposed as well. All data were derived from the mining data base in which differentiation between lithology and sedimentary environments was rather weak. For this reason, the methodological proposals are much more important than details of the sedimentation model in the present paper. Nevertheless, they did reveal some interesting phenomena which may prove important in the reconstruction of peat/lignite environmental conditions. First of all, the presence of cyclicity in the sedimentation model, i.e., cyclic alternation of channel and overbank deposits, represents a fluvial environment. It was also confirmed that the lacustrine subenvironment was cut off from a supply of clastic material by various types of mire barriers. Additionally, our analysis revealed new facts: (i these barriers also existed between lakes in which either carbonate or clay sedimentation predominated; (ii there was no barrier between rivers and lakes in which clay sedimentation predominated; (iii barriers were less efficient in alluvial fan areas but were perfectly tight in regions of phytogenic or carbonate sedimentation; (iv groundwater, rather than surface flow

  18. Mechanism of the Topotactic Formation of gamma-Zirconium Phosphate Covalently Pillared with Diphosphonate Groups.

    Science.gov (United States)

    Alberti, G.; Giontella, E.; Murcia-Mascarós, S.; Vivani, R.

    1998-09-07

    The topotactic reaction of gamma-ZrPO(4)[O(2)P(OH)(2)].2H(2)O (gamma-ZrP) with benzenediphosphonic acid was examined in water and in acetone-water mixtures. This reaction was found to take place in water only on the external surface of the microcrystals, and pillared compounds were never obtained, even after very long reaction times. On the contrary, covalently pillared compounds were quickly obtained in acetone-water mixtures. The mechanism of the latter topotactic reaction was investigated by determining the rate of the phosphate groups released and the rate of the benzenediphosphonates taken up by gamma-ZrP over a long time (50 days). These data showed that pillared derivatives of gamma-ZrP can be obtained because colloidal dispersions of exfoliated lamellae are formed in acetone-water mixtures. The diphosphonate group acts initially as a monovalent species, replacing only one dihydrogen phosphate group on the surface of the exfoliated gamma-lamellae. The colloidal and partially derivatized lamellae thus formed can interact with each other by forming polylamellar pillared systems. When the number of pillared lamellae exceeds a given value (usually 5-6), flocculation of the colloidal gamma-ZrP takes place. Topotactic reactions between packets of pillared lamellae may also continue in the flocculated system. Therefore, the average number of the pillared lamellae slowly increases over time.

  19. Low-temperature pyrolysis of oily sludge: roles of Fe/Al-pillared bentonites

    Directory of Open Access Journals (Sweden)

    Jia Hanzhong

    2017-09-01

    Full Text Available Pyrolysis is potentially an effective treatment of oily sludge for oil recovery, and the addition of a catalyst is expected to affect its pyrolysis behavior. In the present study, Fe/Al-pillared bentonite with various Fe/Al ratios as pyrolysis catalyst is prepared and characterized by XRD, N2 adsorption, and NH3-TPD. The integration of Al and Fe in the bentonite interlayers to form pillared clay is evidenced by increase in the basal spacing. As a result, a critical ratio of Fe/Al exists in the Fe/Al-pillared bentonite catalytic pyrolysis for oil recovery from the sludge. The oil yield increases with respect to increase in Fe/Al ratio of catalysts, then decreases with further increasing of Fe/Al ratio. The optimum oil yield using 2.0 wt% of Fe/Al 0.5-pillared bentonite as catalyst attains to 52.46% compared to 29.23% without catalyst addition in the present study. In addition, the addition of Fe/Al-pillared bentonite catalyst also improves the quality of pyrolysis-produced oil and promotes the formation of CH4. Fe/Al-pillared bentonite provides acid center in the inner surface, which is beneficial to the cracking reaction of oil molecules in pyrolysis process. The present work implies that Fe/Al-pillared bentonite as addictive holds great potential in industrial pyrolysis of oily sludge.

  20. The Los Alamos Science Pillars The Science of Signatures

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Joshua E. [Los Alamos National Laboratory; Peterson, Eugene J. [Los Alamos National Laboratory

    2012-09-13

    As a national security science laboratory, Los Alamos is often asked to detect and measure the characteristics of complex systems and to use the resulting information to quantify the system's behavior. The Science of Signatures (SoS) pillar is the broad suite of technical expertise and capability that we use to accomplish this task. With it, we discover new signatures, develop new methods for detecting or measuring signatures, and deploy new detection technologies. The breadth of work at Los Alamos National Laboratory (LANL) in SoS is impressive and spans from the initial understanding of nuclear weapon performance during the Manhattan Project, to unraveling the human genome, to deploying laser spectroscopy instrumentation on Mars. Clearly, SoS is a primary science area for the Laboratory and we foresee that as it matures, new regimes of signatures will be discovered and new ways of extracting information from existing data streams will be developed. These advances will in turn drive the development of sensing instrumentation and sensor deployment. The Science of Signatures is one of three science pillars championed by the Laboratory and vital to supporting our status as a leading national security science laboratory. As with the other two pillars, Materials for the Future and Information Science and Technology for Predictive Science (IS&T), SoS relies on the integration of technical disciplines and the multidisciplinary science and engineering that is our hallmark to tackle the most difficult national security challenges. Over nine months in 2011 and 2012, a team of science leaders from across the Laboratory has worked to develop a SoS strategy that positions us for the future. The crafting of this strategy has been championed by the Chemistry, Life, and Earth Sciences Directorate, but as you will see from this document, SoS is truly an Institution-wide effort and it has engagement from every organization at the Laboratory. This process tapped the insight and

  1. Enhancing Carbon Reactivity in Mercury Control in Lignite-Fired Systems

    Energy Technology Data Exchange (ETDEWEB)

    Chad Wocken; Michael Holmes; John Pavlish; Jeffrey Thompson; Katie Brandt; Brandon Pavlish; Dennis Laudal; Kevin Galbreath; Michelle Olderbak

    2008-06-30

    This project was awarded through the U.S. Department of Energy (DOE) National Energy Technology Laboratory Program Solicitation DE-PS26-03NT41718-01. The Energy & Environmental Research Center (EERC) led a consortium-based effort to resolve mercury (Hg) control issues facing the lignite industry. The EERC team-the Electric Power Research Institute (EPRI); the URS Corporation; the Babcock & Wilcox Company; ADA-ES; Apogee; Basin Electric Power Cooperative; Otter Tail Power Company; Great River Energy; Texas Utilities; Montana-Dakota Utilities Co.; Minnkota Power Cooperative, Inc.; BNI Coal Ltd.; Dakota Westmoreland Corporation; the North American Coal Corporation; SaskPower; and the North Dakota Industrial Commission-demonstrated technologies that substantially enhanced the effectiveness of carbon sorbents to remove Hg from western fuel combustion gases and achieve a high level ({ge} 55% Hg removal) of cost-effective control. The results of this effort are applicable to virtually all utilities burning lignite and subbituminous coals in the United States and Canada. The enhancement processes were previously proven in pilot-scale and limited full-scale tests. Additional optimization testing continues on these enhancements. These four units included three lignite-fired units: Leland Olds Station Unit 1 (LOS1) and Stanton Station Unit 10 (SS10) near Stanton and Antelope Valley Station Unit 1 (AVS1) near Beulah and a subbituminous Powder River Basin (PRB)-fired unit: Stanton Station Unit 1 (SS1). This project was one of three conducted by the consortium under the DOE mercury program to systematically test Hg control technologies available for utilities burning lignite. The overall objective of the three projects was to field-test and verify options that may be applied cost-effectively by the lignite industry to reduce Hg emissions. The EERC, URS, and other team members tested sorbent injection technologies for plants equipped with electrostatic precipitators (ESPs) and

  2. Perspectives of the non-energetic use of lignite in Germany

    Energy Technology Data Exchange (ETDEWEB)

    Keller, D.; Sailer, B. [RWE Power AG, Essen (Germany)

    2013-11-01

    RWE Power AG as integral part of RWE Generation SE has been active in the development and commercialization of coal gasification routes for many years. RWE Generation SE is one of Europe's leading electricity producers and combines the expertise of the power plant specialists Essent (NL), RWE npower (UK) and RWE Power (D). A globally increasing freight traffic and accompanying fuel demand is anticipated in the future. This higher demand will probably result in an increase in crude oil price in the course of the next years. There will also be a disproportionately high increase in fuel prices additionally to the increase in the crude oil price due to an increasing treatment effort within refineries. Therefore the substitution of crude oil becomes more and more attractive in view of economical perspectives and security of supply. Crude oil is not only to be substituted as feedstock for fuels but also for the chemical industry. Coal has been and will be the most important feedstock for this. Especially its gasification enables various routes. In Germany there is also an interesting perspective for Coal-to-Liquids and Coal-to-Gas or CtL/CtG as the non-energetic use of coal is abbreviated. Lignite is available regardless of any market impacts and currently faces a change in its use for power generation due to the increasing use of renewable energies. Hence lignite is an attractive feedstock for CtL/CtG in Germany. The construction of a commercial size CtL/CtG plant means a billion Euro investment. So a reliable economic evaluation is inevitable. Today all CtL/CtG routes miss commercial competitiveness to the conventional production by some ten percents. In case the current upward price trend of crude oil continues CtL/CtG might become viable in the near future. The production of synthetic fuels appears most attractive in view of a substantial market potential. The further commercialization of gasification routes in Germany requires R and D activities especially

  3. Optimization of pillar electrodes in subretinal prosthesis for enhanced proximity to target neurons

    Science.gov (United States)

    Flores, Thomas; Lei, Xin; Huang, Tiffany; Lorach, Henri; Dalal, Roopa; Galambos, Ludwig; Kamins, Theodore; Mathieson, Keith; Palanker, Daniel

    2018-06-01

    Objective. High-resolution prosthetic vision requires dense stimulating arrays with small electrodes. However, such miniaturization reduces electrode capacitance and penetration of electric field into tissue. We evaluate potential solutions to these problems with subretinal implants based on utilization of pillar electrodes. Approach. To study integration of three-dimensional (3D) implants with retinal tissue, we fabricated arrays with varying pillar diameter, pitch, and height, and implanted beneath the degenerate retina in rats (Royal College of Surgeons, RCS). Tissue integration was evaluated six weeks post-op using histology and whole-mount confocal fluorescence imaging. The electric field generated by various electrode configurations was calculated in COMSOL, and stimulation thresholds assessed using a model of network-mediated retinal response. Main results. Retinal tissue migrated into the space between pillars with no visible gliosis in 90% of implanted arrays. Pillars with 10 μm height reached the middle of the inner nuclear layer (INL), while 22 μm pillars reached the upper portion of the INL. Electroplated pillars with dome-shaped caps increase the active electrode surface area. Selective deposition of sputtered iridium oxide onto the cap ensures localization of the current injection to the pillar top, obviating the need to insulate the pillar sidewall. According to computational model, pillars having a cathodic return electrode above the INL and active anodic ring electrode at the surface of the implant would enable six times lower stimulation threshold, compared to planar arrays with circumferential return, but suffer from greater cross-talk between the neighboring pixels. Significance. 3D electrodes in subretinal prostheses help reduce electrode-tissue separation and decrease stimulation thresholds to enable smaller pixels, and thereby improve visual acuity of prosthetic vision.

  4. Acid–base properties of pillared interlayered clays with single and mixed Zr–Al oxide pillars prepared from Tunisian-interstratified illite–smectite

    Directory of Open Access Journals (Sweden)

    Saida Mnasri

    2017-12-01

    Full Text Available Interstratified illite–smectite clay samples from Tunisia have been used in order to prepare Al, Zr and Zr–Al-pillared clays. Several Al/metal, OH/metal ratios were used in order to investigate the effect on the chemical and physical properties, specifically the point of zero charge (PZC of the synthesized pillared clays. The structure of the pillared materials is studied by XRD and cationic exchange capacity. The textural property is investigated by the nitrogen adsorption/desorption method. The acid–base chemistry “surface acidity” of these products was analysed by using mass and potentiometric titration in order to determine the PZC and the equilibrium constants (pKa of each sample. The resulting materials exhibited basal spacings in the range of 17.4–20.5 Å, with high surface areas (134–199 m2 g−1. Titration curves obtained by acid–base potentiometric titration for the starting material showed an indistinct cross-over point at about pH = 7.3, whereas in the case of pillared samples, points were observed at the acidic region between 4 and 6. In addition, the calculated pKas values of pillared clays show a shifting to the acidic values compared to the untreated sample.

  5. Xenon-129 NMR study of the microporous structure of clays and pillared clays

    International Nuclear Information System (INIS)

    Tsiao, C.; Carrado, K.A.

    1990-01-01

    129 Xe NMR studies have been carried out using xenon gas adsorbed in clays and pillared clays. Data from the measurements provide information on the pore structure of clays before and after pillaring. The results indicate that the effective pore diameter of montmorillonite increases, for example, from 5.4 Angstrom to 8.0 Angstrom after pillaring cheto-montmorillonite with aluminum polyoxohydroxy Keggin cations. The data are consistent with X-ray powder diffraction results, which show a corresponding increase in the interlamellar gallery height from 5.6 Angstrom to 8.4 Angstrom

  6. InGaN micro-LED-pillar as the building block for high brightness emitters

    KAUST Repository

    Shen, Chao; Cha, Dong Kyu; Ng, Tien Khee; Ooi, Boon S.; Yang, Yang

    2013-01-01

    In summary, we confirmed the improved electrical and optical characteristics, with reduced efficiency droop in InGaN μLED-pillars when these devices were scaled down in size. We demonstrated that strain relief contributed to further improvement in EQE characteristics in small InGaN μLED-pillars (D < 50 μm), apart from the current spreading effect. The μLED-pillar can be deployed as the building block for large effective-area, high brightness emitter. © 2013 IEEE.

  7. Response of surface springs to longwall coal mining Wasatch Plateau, Utah

    International Nuclear Information System (INIS)

    Kadnuck, L.L.M.

    1994-01-01

    High-extraction longwall coal mining creates zones in the overburden where strata bend, fracture, or cave into the mine void. These physical alterations to the overburden stratigraphy have associated effects on the hydrologic regime. The US Bureau of Mines (SBM) studied impacts to the local hydrologic system caused by longwall mining in the Wasatch Plateau, Utah. Surface springs in the vicinity of two coal mines were evaluated for alterations in flow characteristics as mining progressed. Fourteen springs located above the mines were included in the study. Eight of the springs were located over longwall panels, four were located over barrier pillars and mains, and two ere located outside the area disturbed by mining. Flow hydrographs for each spring were compared to climatic data and time of undermining to assess if mining in the vicinity had influenced flow. Heights of fracturing and caving in the overburden resulting from seam extraction were calculated using common subsidence formulas, and used in conjunction with elevations of springs to assess if fracturing influenced the water-bearing zones studied. One spring over a panel exhibited a departure from a normally-shaped hydrograph after being undermined. Springs located over other mine structures, or outside the mine area did not show discernible effects from mining. The limited response of the springs was attributed to site-specific conditions that buffered mining impacts including the elevation of the springs above the mine level, and presence of massive sandstones and swelling clays in the overburden materials

  8. Planning criteria for open pit mines under special consideration of slope stability and controlled blasting

    Energy Technology Data Exchange (ETDEWEB)

    Weise, H

    1986-04-01

    The criteria which influence the economics of a future surface mining operation are discussed; these include the size of the mine and the depth of the deposit. The methods of working are outlined - single bench, multiple bench - and choices of haulage equipment (trucks vs. conveyors) are discussed. For a mine using conveyors, the slope of the open pit will affect the operating cost. Pumps will be required to dewater the strata; it will be necessary to take steps to ensure slope stability. Bucket wheel excavators will be impeded by the presence of consolidated material, which may be best removed by shatter blasting. An example is given of the use of shatter blasting at the Neyveli lignite mine in Tamil Nadu, India. 5 references.

  9. Characterization of dust samples from a coal strip mine using a resuspension chamber

    Directory of Open Access Journals (Sweden)

    Martin Civiš

    2017-06-01

    Full Text Available A metallic cylindrical resuspension chamber (V = 0.437 m3, S = 0.35 m2, S/V = 8.38 was constructed to disperse samples of soil and various kinds of dust. The chamber allows on-line determination of number/mass size distribution of aerosol particles formed by dispersion and subsequent sampling of size-segregated particles on filter media. The samples tested were lignite, power plant flue ash and overburden soil from the Nastup coal strip mine in Northern Bohemia. About 20 mg of the individual samples were pneumatically dispersed by 0.5 liter of pressurized air inside the chamber under defined temperature and humidity conditions. Then the dynamics of aerosol size distributions was recorded using an aerodynamic particle sizer with a frequency of 5 seconds. The lignite and flue ash contributed most to the mass of atmospheric aerosol particles smaller than 10/2.5 micrometer – PM10/ PM2.5. The re-suspended mass of the samples varied between 0.001% for overburden soil and 0.32% for mine road soil. The aerosolized lignite and flue ash samples, sampled by a Harvard Impactor and a Personal Cascade Impactor Sampler, revealed that the ash contained higher amounts of fine particles than the lignite and subsequent chemical analyses, carried out using SEM-EDX, reveals that the PM2.5 fraction formed by dispersion of the ash samples had the highest content of sulphur, and PM10 was dominated by Si. PM10 was closest to mullite, while the PM2.5 fraction contained sulphides, pyrites, pyrrhotites and polytypes of sulphide. The PM1 fraction was dominated by quartz glass. The fractions of sizes 2.5–1 μm and 0.5–0.25 μm were dominated by Si and S, respectively.

  10. New pillars of evolutionary theory in the light of genomics

    International Nuclear Information System (INIS)

    Lopez Carrascal, Camilo Ernesto

    2011-01-01

    The evolutionist theory proposed by Darwin is one of the fundamental pillars in biology. Darwin's theory was solidified with the modern synthesis of evolutionary biology thanks to the rediscovery of Mendel's work, which laid the genetic basis of heredity. In recent years, great progress has been acquired in the sequencing and analyses of complete genomes, which have provided several elements to discuss some Darwinists tenets of evolution. The evidence of gene duplication and whole-genome duplication, the horizontal gene transfer and the endosymbiosis process question the idea that evolution proceeds through the gradual accumulation of infinitesimally small random changes. The new evidence of neutral selection on the genomics context reveals other mechanisms of evolution not necessarily related with the idea of progress or with an adaptationist program as was originally stated by the Darwin's theory. in this paper, I present these and other concepts such as gene regulation, molecular mechanisms of development and some environmental aspects (epigenesis and phenotypic plasticity) as starting points to think in the necessity to update the evolutionary theory which in my opinion should be more inclusive, pluralistic and consistent with our current knowledge.

  11. Mine Water Treatment in Hongai Coal Mines

    OpenAIRE

    Dang Phuong Thao; Dang Vu Chi

    2018-01-01

    Acid mine drainage (AMD) is recognized as one of the most serious environmental problem associated with mining industry. Acid water, also known as acid mine drainage forms when iron sulfide minerals found in the rock of coal seams are exposed to oxidizing conditions in coal mining. Until 2009, mine drainage in Hongai coal mines was not treated, leading to harmful effects on humans, animals and aquatic ecosystem. This report has examined acid mine drainage problem and techniques for acid mine ...

  12. Residential damage in an area of underground coal mining

    International Nuclear Information System (INIS)

    Padgett, M.F.

    1988-01-01

    In order to estimate the potential for future subsidence-related residential damage, a statistical analysis of past residential damage in the Boulder-Weld, Colorado, coal field was performed. The objectives of this study were to assess the difference in damage severity and frequency between undermined and non-undermined areas, and to determine, where applicable, which mining factors significantly influence the severity and frequency of residential damage. The results of this study suggest that undermined homes have almost three times the risk of having some type of structural damage than do non-undermined homes. The study also indicated that both geologic factors, such as the ratio of sandstone/claystone in the overburden, and mining factors, such as the mining feature (room, pillar, entry, etc.), can significantly affect the severity of overlying residential damage. However, the results of this study are dependent on local conditions and should not be applied elsewhere unless the geologic, mining, and residential conditions are similar

  13. Geotechnical investigations on backfill materials in the Asse salt mine

    International Nuclear Information System (INIS)

    Kappei, G.

    1986-01-01

    The compression behaviour of rock salt grit is being investigated by compression tests at the Asse salt mine. The various test parameters are introduced and their results are discussed. The permeability of rock salt grit with saturated NaCl-brine in dependency upon the grain size and compactness, resp. the porosity, is being determined at the Asse salt mine. The test equipment and the results determined here are shown. In addition to laboratory tests, geotechnical investigations are taking place in a carnallitic chamber of the Asse salt mine which had been backfilled in earlier years. They chiefly concern measurements of the deformation rates in drifts - which were mined between the chambers in remaining pillars - as well as horizontal deformation measurements in the backfilling. (orig./DG)

  14. Towards total productive maintenance in the Eastern European mining industry

    Energy Technology Data Exchange (ETDEWEB)

    Buck, J.D. [Kepner-Tregoe (United Kingdom) Ltd., Windsor

    1999-08-01

    An European Union consultancy project was undertaken to install a `best-in-class` maintenance system for the lignite mines of Romania. The project, funded by PHARE, started with a critical analysis of the maintenance and repair systems of equipment in both the open-pit and underground mines operated by RALO (Regia Autonoma a Lignitului Octenia). This study paved the way for the introduction of a computerised maintenance system and the inception of a planned preventative maintenance scheme. A development strategy leading by a structural methodology towards predictive maintenance and total productive maintenance was drawn up and attention was given to multi-skilling, training and further facilitating activities to enable the success of the total productive maintenance strategy. An abridged version of the paper was presented at MAINTE 97, held in Birmingham, UK in 1997. 5 refs., 5 figs., 1 tab.

  15. Surface mining machines problems of maintenance and modernization

    CERN Document Server

    Rusiński, Eugeniusz; Moczko, Przemysław; Pietrusiak, Damian

    2017-01-01

    This unique volume imparts practical information on the operation, maintenance, and modernization of heavy performance machines such as lignite mine machines, bucket wheel excavators, and spreaders. Problems of large scale machines (mega machines) are highly specific and not well recognized in the common mechanical engineering environment. Prof. Rusiński and his co-authors identify solutions that increase the durability of these machines as well as discuss methods of failure analysis and technical condition assessment procedures. "Surface Mining Machines: Problems in Maintenance and Modernization" stands as a much-needed guidebook for engineers facing the particular challenges of heavy performance machines and offers a distinct and interesting demonstration of scale-up issues for researchers and scientists from across the fields of machine design and mechanical engineering.

  16. Reactivity of chars prepared from the pyrolysis of a Victorian lignite under a wide range of conditions

    Energy Technology Data Exchange (ETDEWEB)

    Wu, H.; Mody, D.; Li, C.; Hayashi, J.; Chiba, T. [Monash University, Vic. (Australia). CRC for Clean Power from Lignite, Dept. of Chemical Engineering

    2000-07-01

    A Loy Yang lignite sample was pyrolysed under a wide range of experimental conditions using a wire-mesh reactor, a fluidised-bed reactor, a drop-tube reformer and a thermogravimetric analyser (TGA). The reactivity of these char samples in CO{sub 2} and air was measured in the TGA as well as in the fluidised-bed reactor. A sample prepared by the physical impregnation of NaCl into the lignite was also used in order to investigate the effect of NaCl in the lignite on the reactivity of the resulting char. Our experimental results indicate that, due to the volatilisation of a substantial fraction of Na in the lignite substrate during pyrolysis, the true catalytic activity of the Na in the lignite substrate should be evaluated by measuring the sodium content in the char after pyrolysis. The char reactivity measured in situ in the fluidised-bed reactor was compared with that of the same char measured separately in the TGA after re-heating the char sample to the same temperature as that in the fluidised-bed. It was found that the re-heating of the char in the TGA reduced the char reactivity.

  17. Concentrations and source apportionment of PM10 and associated elemental and ionic species in a lignite-burning power generation area of southern Greece.

    Science.gov (United States)

    Argyropoulos, G; Grigoratos, Th; Voutsinas, M; Samara, C

    2013-10-01

    Ambient concentrations of PM10 and associated elemental and ionic species were measured over the cold and the warm months of 2010 at an urban and two rural sites located in the lignite-fired power generation area of Megalopolis in Peloponnese, southern Greece. The PM10 concentrations at the urban site (44.2 ± 33.6 μg m(-3)) were significantly higher than those at the rural sites (23.7 ± 20.4 and 22.7 ± 26.9 μg m(-3)). Source apportionment of PM10 and associated components was accomplished by an advanced computational procedure, the robotic chemical mass balance model (RCMB), using chemical profiles for a variety of local fugitive dust sources (power plant fly ash, flue gas desulfurization wet ash, feeding lignite, infertile material from the opencast mines, paved and unpaved road dusts, soil), which were resuspended and sampled through a PM10 inlet onto filters and then chemically analyzed, as well as of other common sources such as vehicular traffic, residential oil combustion, biomass burning, uncontrolled waste burning, marine aerosol, and secondary aerosol formation. Geological dusts (road/soil dust) were found to be major PM10 contributors in both the cold and warm periods of the year, with average annual contribution of 32.6 % at the urban site vs. 22.0 and 29.0 % at the rural sites. Secondary aerosol also appeared to be a significant source, contributing 22.1 % at the urban site in comparison to 30.6 and 28.7 % at the rural sites. At all sites, the contribution of biomass burning was most significant in winter (28.2 % at the urban site vs. 14.6 and 24.6 % at the rural sites), whereas vehicular exhaust contribution appeared to be important mostly in the summer (21.9 % at the urban site vs. 11.5 and 10.5 % at the rural sites). The highest contribution of fly ash (33.2 %) was found at the rural site located to the north of the power plants during wintertime, when winds are favorable. In the warm period, the highest contribution of fly ash was found at the

  18. Extending mine life

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    Mine layouts, new machines and techniques, research into problem areas of ground control and so on, are highlighted in this report on extending mine life. The main resources taken into account are coal mining, uranium mining, molybdenum and gold mining

  19. Uranium mining

    International Nuclear Information System (INIS)

    2008-01-01

    Full text: The economic and environmental sustainability of uranium mining has been analysed by Monash University researcher Dr Gavin Mudd in a paper that challenges the perception that uranium mining is an 'infinite quality source' that provides solutions to the world's demand for energy. Dr Mudd says information on the uranium industry touted by politicians and mining companies is not necessarily inaccurate, but it does not tell the whole story, being often just an average snapshot of the costs of uranium mining today without reflecting the escalating costs associated with the process in years to come. 'From a sustainability perspective, it is critical to evaluate accurately the true lifecycle costs of all forms of electricity production, especially with respect to greenhouse emissions, ' he says. 'For nuclear power, a significant proportion of greenhouse emissions are derived from the fuel supply, including uranium mining, milling, enrichment and fuel manufacture.' Dr Mudd found that financial and environmental costs escalate dramatically as the uranium ore is used. The deeper the mining process required to extract the ore, the higher the cost for mining companies, the greater the impact on the environment and the more resources needed to obtain the product. I t is clear that there is a strong sensitivity of energy and water consumption and greenhouse emissions to ore grade, and that ore grades are likely to continue to decline gradually in the medium to long term. These issues are critical to the current debate over nuclear power and greenhouse emissions, especially with respect to ascribing sustainability to such activities as uranium mining and milling. For example, mining at Roxby Downs is responsible for the emission of over one million tonnes of greenhouse gases per year and this could increase to four million tonnes if the mine is expanded.'

  20. Surface tension-induced PDMS micro-pillars with controllable tips and tilt angles

    KAUST Repository

    Li, Huawei; Fan, Yiqiang; Conchouso Gonzalez, David; Foulds, Ian G.

    2013-01-01

    This paper reports a novel method to fabricate three-dimensional (3D) polydimethylsiloxane (PDMS) micro-pillars using a CO2 laser-machined poly(methyl methacrylate) (PMMA) mold with through-holes. This method eliminates the requirements of expensive and complicated facilities to fabricate a 3D mold. The micro-pillars were formed by the capillary force that draws PDMS into the through-holes of the PMMA mold. The tilt angles of the micro-pillars depend on the tilt angles of the through-holes in the mold, and the concave and convex micro-lens tip shapes of the PDMS micro-pillars can be modified by changing the surface wettability of the PMMA through-holes.